

Introduction Gaming screens are certainly a big focus in the monitor market at the moment, spurred on by the arrival of new variable refresh rate technologies from NVIDIA (G-sync) and AMD (FreeSync). Over the last year we've seen fast TN Film gaming screens released with new 27" 2560 x 1440 panels. The Asus ROG Swift PG278Q and BenQ XL2730Z spring to mind as two excellent gaming screens built around this resolution, and combining it with variable refresh rate support. As well as developments in the TN Film gaming space we've also finally seen the release of high refresh rate IPS-type panels, in the form of models like the Acer XB270HU and Asus MG279Q - again with G-sync and FreeSync respectively. These have brought about some positive changes in the gaming space, finally allowing users to experience the benefits of IPS technology from a gaming display. Also within the last year we've seen a steady increase in new ultra-wide screens offering 21:9 aspect ratios and some large screen sizes up to 34". Normal flat models like the LG 34UM95 were followed by a new breed of curved 34" screens like the Dell U3415W for instance. The ultra-wide screens have attracted a lot of interest from users as a good substitute for dual-screen operation, while also offering a very interesting possibility for multimedia and gaming thanks to their format and high 3440 x 1440 resolutions. Curved screens provide some immersion improvements (in our opinion) and feel a little more comfortable than flat models given their size and width. A few manufacturers are now starting to invest in 34" screens which are specifically being targeted at gamers. The first to be released is the new Acer Predator XR341CK, a 34" curved screen built around an IPS panel and supporting AMD FreeSync variable refresh rate technology. Acer have also boosted the refresh rate a little - well, by 25% in fact from 60Hz to 75Hz. The screen is provided with various extras and features which we will look at throughout the course of this review. Note: a G-sync model is also planned in the near future, the Predator X34 as it will now be known, not the XR341CKA as previously thought. It is largely the same screen, but will feature a G-sync module instead of AMD FreeSync being supported. Specs and features have yet to be finalised, but from what we know at the moment It will offer more limited connectivity with only DisplayPort and HDMI 1.4 expected. The Picture in Picture, Picture by Picture and Daisy Changing options will not be available. However it will feature an ULMB strobe backlight (Ultra Low Motion Blur) mode as part of the G-sync module for blur reduction benefits. We will hopefully have chance to have a look at the Predator X34 at some point although most of the performance should be identical to the model reviewed here. It is being provided as a more suitable option for NVIDIA users. Retail price is likely to be a little higher though given the additional cost of the G-sync module. If you appreciate the review and enjoy reading and like our work, we would welcome a donation to the site to help us continue to make quality and detailed reviews for you. We worked overtime to bring you this review nice and quickly as we know how excited people were to see how this screen performs. Check Pricing and Buy - Direct Links Amazon USA | Amazon UK | Amazon GER | Amazon CAN TFTCentral is a participant in the Amazon Services LLC Associates Programme, an affiliate advertising programme designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com, Amazon.co.uk, Amazon.de, Amazon.ca and other Amazon stores worldwide. We also participate in a similar scheme for Overclockers.co.uk.



Specifications and Features The following table gives detailed information about the specs of the screen: Monitor Specifications Size 34"WS (87 cm) Panel Coating Light AG coating Aspect Ratio 21:9 Interfaces 1x DisplayPort 1.2a (+1 DP out)

1x Mini DisplayPort

1x HDMI 1.4 1x HDMI 2.0 1x MHL 2.0 Resolution 3440 x 1440 Pixel Pitch 0.233 mm Design colour Matte black bezel with dark silver aluminium trim, and light silver aluminium stand Response Time 4ms G2G Ergonomics Tilt, 130mm height Static Contrast Ratio 1000:1 Dynamic Contrast Ratio 100 million:1 VESA Compatible Yes 100mm Brightness 300 cd/m2 Accessories Power, DisplayPort, HDMI and USB cables Viewing Angles 178 / 178 Panel Technology LG.Display AH-IPS Weight net: 9.9Kg Backlight Technology W-LED Physical Dimensions (WxHxD) with stand:

825.1 x 455.9 - 585.9 x 309 mm Colour Depth 1.07b Refresh Rate 75z max

FreeSync range 30 - 75Hz Special Features 4x USB 3.0 ports (with charging capability), headphone port, AMD FreeSync, 2x 7W speakers, ambient light system Colour Gamut Standard gamut

~sRGB, ~72% NTSC The XR341CK offers a very good range of connectivity options with DisplayPort, Mini DisplayPort and 1x HDMI 1.4, 1x HDMI 2.0 (with MHL support) provided. There is also a DisplayPort out connection for daisy chaining multiple screens if you want. The screen is not limited to DisplayPort-only like all current G-sync screens are (a limitation of the current G-sync module from NVIDIA), as FreeSync allows for other connections to still be offered on the screen, even though the DisplayPort / Mini DP are the only one to support the actual FreeSync technology. That is certainly a pro for FreeSync over G-sync. Note that the forthcoming Predator X34 (G-sync version) is expected to feature G-sync rev2 and therefore offer an HDMI connection along side the DisplayPort. Still, connectivity on the G-sync version is far more limited than provided here. The digital interfaces are HDCP certified for encrypted content and the video cables are provided in the box for DisplayPort and HDMI, along with a USB cable.

Above: Acer XR341CK boxed up The screen has an external power supply brick which comes packaged along with the power cable you need. There are also 4x USB 3.0 ports, located on the back of the screen next to the video and power connections. Two have charging capabilities as well. There are also some 2x 7W DTS sound integrated speakers, but no further extras like card readers, ambient light sensors or human motion sensors provided as those are more aimed at office uses, while this is primarily a gaming screen. Below is a summary of the features and connections of the screen: Feature Yes / No Feature Yes / No Tilt adjust DVI Height adjust HDMI Swivel adjust D-sub Rotate adjust DisplayPort VESA compliant Component USB 2.0 Ports Composite USB 3.0 Ports Audio connection Card Reader HDCP Support Ambient Light Sensor MHL Support Human Motion Sensor Integrated Speakers Touch Screen PiP / PbP Factory Calibration Blur Reduction Mode Hardware calibration G-Sync Uniformity correction FreeSync



Design and Ergonomics







Above: front views of the screen. Click for larger versions The XR341CK comes in a black and silver design with a mixture of matte and glossy plastics used and some aluminium for the base. The screen has a "borderless" black plastic edge around the sides and top measuring ~1.5mm in thickness. Inside of that the panel also has a ~11mm border before the image starts, giving a total of ~12.5mm around the sides as a border. Along the bottom edge of the screen a matte black plastic is used with a dark silver aluminium style trim in the middle as you can see from the pictures above. This measures ~24.5mm in thickness (with the panel having an additional ~2.5mm edge as well along the bottom). There is a shiny silver "acer" logo in the middle of the lower bezel and an almost-invisible power logo next to where the power LED is in the bottom right hand corner. The power LED is very small and glows blue during normal operation, amber in standby. The OSD control buttons are located underneath the bottom edge in the right hand corner.

Above: rear view of the screen The back of the screen is a glossy black plastic which attracts finger prints and dust quite easily. Although since it's on the back of the screen it doesn't prove a problem when it's sat on your desk really. The stand attaches at the back and is screwed in to place by 4 screws (with little rubber covers) since the whole screen is heavy and a quick release mechanism would probably not be sufficient to keep it safe. We will look at the stand in a moment. The connections for video etc are on the back of the screen near the bottom as you can see from the above image.

Above: side views The screen itself is fairly thin given the LED backlighting and external power supply. The stand however is very deep and since it has a 3 pronged style you do need to have all 3 points on your desk. Had it been a flat, square stand you could have in theory had it overhanging the edge of the desk a bit (assuming you've got a wall behind it) if you wanted to move it back a little bit. As it is, on fairly shallow desks it sits quite a long way forward towards the user. The base is 309mm (30.9cm) deep so you probably need a fairly deep desk to be able to have it at a comfortable distance away. It looks stylish and pretty sleek, but it was a bit impractical we felt for some people.

Above: rear views of the stand. Click for larger versions The stand is a silver aluminium frame with black plastic central section, and provides a strong, sturdy and heavy base for the big display. It can be unscrewed if you want and the screen is VESA 100mm compliant for wall or arm mounting. The stand has a useful carry handle at the top as the screen is big and very heavy. There is a cable tidy hole at the bottom as well. Above: view from above. The screens curvature can be seen from the above image, along with some other photos of the display. There are some ergonomic adjustments offered from the stand, with the main tilt and height adjustments being present.

Above: full range of tilt adjustment shown. Click for larger versions The tilt function is smooth but quite stiff to move, but it does offer a wide range of angles to choose from as shown above. Height adjustment is also smooth but very stiff to move, to the point of almost having to force it to get it moving at all. At the lowest height setting the bottom edge of the screen is approximately 40mm from the edge of the desk. At the maximum setting it is ~190mm, and so there is a 150 mm total adjustment range available here. There are no side to side swivel or rotate adjustments offered. Swivel would have been handy since the base is heavy and you can't really re-position the base very often without it being a pain. Rotation into portrait mode would have been impractical on a screen this size anyway so isn't missed. A summary of the screens ergonomic adjustments is shown below: Function Range Smoothness Ease of Use Tilt Yes Smooth Quite stiff Height 150mm Smooth Very Stiff Swivel n/a - - Rotate n/a - - Overall Reasonable range of adjustments offered, although stiff to move. The materials were of a good standard and the build quality felt good as well. There was a whining noise from the screen when running at lower brightness settings. It seemed to only kick in below about 40 brightness and below, and you can certainly hear it as you get lower. It's not very loud, and sounds more like a system fan or something like that. The pitch changed a little depending on the content on the screen at the time. The whole screen remained cool even during prolonged which was pleasing.

Above: rear views of the screen showing connections. The back of the screen provides all the connections as shown above. There are, from left to right - HDMI 2.0, HDMI 1.4, Mini DisplayPort, DisplayPort in, DisplayPort out (for Daisy chaining), power connection (external brick provided), headphone out, USB upstream, 2x USB 3.0, 2x USB 3.0 with charging capabilities. One gripe is that the DisplayPort connection is close to the upper edge of the inset section. Since the pressable button on most DP cables is on the top side (press to release it from connection), that gets obscured by the over-hanging plastic edge above it. When it's plugged in it's tricky to get to the button to release the connection without using a flat edged tool or knife or something to press the button. The cable provided with the screen does not have this lock button according to Acer (they told us after we had raised this point with them), although we didn't check and were just using an existing cable we had connected from our system. The screen features an ambient light feature which we quite liked. Not something we've seen before on other screens but a fairly nifty idea we thought. An LED strip of lights is located along most of the bottom edge of the screen which can be controlled via the OSD menu as shown above. When turned on you can change the colour and style of this light, which provides a nice attractive glow beamed on to the desk below. The colour can be changed to red, green, blue, white, orange, a random setting and also 'MNT status' (whatever that means!). You can also change the style of the light, whether it's fixed on, breathing, flashing, or ripple. The ripple is quite nice, moving from end to end like the light on the front of KITT in Knight Rider (old school 80's reference!) You can also change the brightness in settings from 1 - 5, and whether the LED stays on when the screen is asleep.



OSD Menu

Above: OSD control buttons on the underside edge of the screen. Click for larger version The OSD menu is accessed and controlled through a series 5 pressable buttons, along with a power on/off button. These are all located on the underside edge of the screen in the bottom right hand corner. There's no labels on the front of the screen other than a very subtle power logo above the power on/off button so sometimes it's a bit tricky to know which button you are pressing. In fact we did find we turned the screen off accidentally a few times, which is even more frustrating since it takes a good 15 seconds or so to power back on! Pressing any of the buttons brings up the first quick launch menu as shown above. From here you can access (from left to right) the game modes, OD overdrive setting, volume control and input selection. Since there are only 5 buttons to press, the last one with the green arrow will move you into another few options shown below: The second half of the quick launch menu is shown above, with options now for all the PiP / PbP modes and then finally the main OSD. It's a bit annoying actually that you have to scroll in to this extra menu to be able to get to the main menu, so it's 3 button presses to even get in to the main menu. You can't change these quick launch options either sadly. Some of the quick launch menus are shown above, for OD mode, volume and input selection. Entering the main menu provides you with a wealth of options to play with. The menu is split down the left hand side into 5 sections, with options available in each shown on the right. At the bottom the icons tell you what each button will now do within the menu. There is also access to the 5 preset modes at the bottom via the green 'e' icon. They are basically just a series of 5 preset modes mostly down to different brightness settings. If you change anything yourself in the OSD then it reverts you to the 'user' mode automatically so you can't really customise the modes how you want unfortunately. The first section in the main OSD menu is the 'picture' menu with options for the eColor management preset modes, brightness and contrast. The low blue light mode and dynamic contrast ratio (ACM) are also provided here if you want to use them. The eColor preset mode menu is shown above for reference, with 5 modes available if you want. The second section is the 'color' menu contains options for the gamma and colour temperature modes as well as adjustments for the RGB levels for calibration. The third 'OSD' section has a few options relating to the menu itself. You can also access a couple of gaming options to display the refresh rate currently running in the top right hand corner (maybe handy when using FreeSync) and also an 'aim point' for shooting games. The 'setting' section has quite a few options in it. You can control the OD overdrive setting here and the PiP/PbP modes. There is also access to the ambient light feature which we looked at in the previous section. Below those options there are some others as also shown, including options for the aspect ratio modes and the low latency mode designed to reduce input lag. The final section contains a bit of info about the current settings of the screen. All in all the menu had a lot of options to play with and the software looked nice and felt modern. It was a bit confusing to navigate sometimes and not that intuitive, having to drill in to different levels and then using lots of arrows back and forth. You sometimes find yourself having to go through many button presses to get to an option you want.

Power Consumption In terms of power consumption the manufacturer lists typical usage of 42.5W, and 0.5W in standby. We carried out our normal tests to establish its power consumption ourselves. State and Brightness Setting Manufacturer Spec (W) Measured Power Usage (W) Default (80%) 42.5 48.8 Calibrated (28%) - 30.7 Maximum Brightness (100%) - 56.3 Minimum Brightness (0%) - 21.8 Standby 0.5 0.5 We tested this ourselves and found that out of the box the screen used 48.8W at the default 80% brightness setting. Once calibrated the screen reached 30.7W consumption, and in standby it used only 0.5W. We have plotted these results below compared with other screens we have tested. The calibrated consumption is very similar to the Dell U3415W (32.1W), although both are a little lower than the 34" flat format LG 34UM95 (42.0W).



Panel and Backlighting Panel Manufacturer LG.Display Colour Palette 1.074 billion Panel Technology AH-IPS Colour Depth 8-bit + FRC Panel Module LM340UW2-SSA1 Colour space Standard gamut Backlighting Type W-LED Colour space coverage (%) ~sRGB, ~72% NTSC Panel Part and Colour Depth The XR341CK features an LG.Display LM340UW2-SSA1 AH-IPS panel which is capable of producing 1.074 billion colours. As we understand it the panel offers an 8-bit colour depth with additional Frame Rate Control (FRC) stage added to support 10-bit content. Keep in mind whether this is practically useable and whether you're ever going to truly use that colour depth. You need to have a full 10-bit end to end workflow to take advantage of it which is still quite expensive to achieve and rare in the market, certainly for your average user. This includes relevant applications and graphics cards as well, so to many people this 10-bit support might be irrelevant. The part is confirmed when dismantling the screen. Incidentally this is the same panel we saw used in the Dell U3415W display as well. Screen Coating The screen coating on the XR341CK is a light anti-glare (AG) offering. It isn't a semi-glossy coating, but it is light as seen on other modern IPS type panels. Thankfully it isn't a heavily grainy coating like some old IPS panels feature and is also lighter than modern TN Film panel coating, including popular gaming screens. It retains its anti-glare properties to avoid too many unwanted reflections of a full glossy coating, but does not produce an too grainy or dirty an image that some thicker AG coatings can. There were some very slight cross-hatching patterns visible on the coating if you looked very closely, but nothing to the extent of what some people find problematic on the U2713HM model.

Backlight Type and Colour Gamut The screen uses a White-LED (W-LED) backlight unit which has become very popular in today's market. This helps reduce power consumption compared with older CCFL backlight units and brings about some environmental benefits as well. The W-LED unit offers a standard colour gamut which is approximately equal to the sRGB colour space. Anyone wanting to work with wider colour spaces would need to consider wide gamut CCFL screens or the newer range of GB-r-LED type displays available now. If you want to read more about colour spaces and gamut then please have a read of our detailed article.

Backlight Dimming and Flicker We tested the screen to establish the methods used to control backlight dimming. Our in depth article talks in more details about a common method used for this which is called Pulse Width Modulation (PWM). This in itself gives cause for concern to some users who have experienced eye strain, headaches and other symptoms as a result of the flickering backlight caused by this technology. We use a photosensor + oscilloscope system to measure backlight dimming control with a high level of accuracy and ease. These tests allow us to establish 1) Whether PWM is being used to control the backlight

2) The frequency and other characteristics at which this operates, if it is used

3) Whether a flicker may be introduced or potentially noticeable at certain settings If PWM is used for backlight dimming, the higher the frequency, the less likely you are to see artefacts and flicker. The duty cycle (the time for which the backlight is on) is also important and the shorter the duty cycle, the more potential there is that you may see flicker. The other factor which can influence flicker is the amplitude of the PWM, measuring the difference in brightness output between the 'on' and 'off' states. Please remember that not every user would notice a flicker from a backlight using PWM, but it is something to be wary of. It is also a hard thing to quantify as it is very subjective when talking about whether a user may or may not experience the side effects.

100% 50% 0%



Above scale = 1 horizontal grid = 5ms At 100% brightness a constant voltage is applied to the backlight. As you reduce the brightness setting to dim the backlight a Direct Current (DC) method is used, as opposed to any form of PWM. This applies to all brightness settings from 100% down to 0%. The screen is flicker free as a result as advertised. Pulse Width Modulation Used No Cycling Frequency n/a Possible Flicker at 100% Brightness No 50% Brightness No 0% Brightness No For an up to date list of all flicker-free (PWM free) monitors please see our Flicker Free Monitor Database.

Contrast Stability and Brightness We wanted to see how much variance there was in the screens contrast as we adjusted the monitor setting for brightness. In theory, brightness and contrast are two independent parameters, and good contrast is a requirement regardless of the brightness adjustment. Unfortunately, such is not always the case in practice. We recorded the screens luminance and black depth at various OSD brightness settings, and calculated the contrast ratio from there. Graphics card settings were left at default with no ICC profile or calibration active. Tests were made using an X-rite i1 Display Pro colorimeter. It should be noted that we used the BasICColor calibration software here to record these, and so luminance at default settings may vary a little from the LaCie Blue Eye Pro report. OSD Brightness Luminance

(cd/m2) Black Point (cd/m2) Contrast Ratio

( x:1) 100 310.64 0.28 1109 90 284.09 0.26 1093 80 259.12 0.24 1080 70 232.67 0.21 1108 60 207.06 0.19 1090 50 179.83 0.16 1124 40 153.35 0.14 1095 30 125.22 0.11 1138 20 97.98 0.09 1089 10 69.03 0.06 1150 0 40.91 0.04 1023 Total Luminance Adjustment Range (cd/m2) 269.73 Brightness OSD setting controls backlight? Total Black Point Adjustment Range (cd/m2) 0.24 Average Static Contrast Ratio 1100:1 PWM Free? Recommended OSD setting for 120 cd/m2 28 The brightness control gave us a very good range of adjustment. At the top end the maximum luminance reached 311 cd/m2 which was even slightly higher than the specified maximum brightness of 300 cd/m2 from the manufacturer. There was a decent 270 cd/m2 adjustment range in total, and so at the minimum setting you could reach down to a low luminance of 41 cd/m2. This should be more than adequate for those wanting to work in darkened room conditions with low ambient light. A setting of 28 in the OSD menu should return you a luminance of around 120 cd/m2 at default settings. It should be noted that the brightness regulation is controlled without the need for Pulse Width Modulation, using a Direct Current (DC) method for all brightness settings between 100 and 0% and so the screen is flicker free as advertised. We have plotted the luminance trend on the graph above. The screen behaves as it should in this regard, with a reduction in the luminance output of the screen controlled by the reduction in the OSD brightness setting. This is a linear relationship as you can see. The average contrast ratio of the screen was excellent for an IPS-type panel with an average of 1100:1. This was mostly stable across the brightness adjustment range as shown above with some fluctuation at the lower brightness settings below 30.



Testing Methodology An important thing to consider for most users is how a screen will perform out of the box and with some basic manual adjustments. Since most users won't have access to hardware colorimeter tools, it is important to understand how the screen is going to perform in terms of colour accuracy for the average user. We restored our graphics card to default settings and disabled any previously active ICC profiles and gamma corrections. The screen was tested at default factory settings using an X-rite i1 Pro Spectrophotometer (not to be confused with the i1 Display Pro colorimeter) combined with LaCie's Blue Eye Pro software suite. An X-rite i1 Display Pro colorimeter was also used to verify the black point and contrast ratio since the i1 Pro spectrophotometer is less reliable at the darker end.

Targets for these tests are as follows: CIE Diagram - validates the colour space covered by the monitors backlighting in a 2D view, with the black triangle representing the displays gamut, and other reference colour spaces shown for comparison

Gamma - we aim for 2.2 which is the default for computer monitors

Colour temperature / white point - we aim for 6500k which is the temperature of daylight

Luminance - we aim for 120 cd/m 2 , which is the recommended luminance for LCD monitors in normal lighting conditions

Black depth - we aim for as low as possible to maximise shadow detail and to offer us the best contrast ratio

Contrast ratio - we aim for as high as possible. Any dynamic contrast ratio controls are turned off here if present

dE average / maximum - as low as possible. If DeltaE >3, the color displayed is significantly different from the theoretical one, meaning that the difference will be perceptible to the viewer. If DeltaE <2, LaCie considers the calibration a success; there remains a slight difference, but it is barely undetectable. If DeltaE < 1, the color fidelity is excellent.



Default Performance and Setup Default settings of the screen were as follows: Monitor OSD Option Default Settings Preset mode (eColor mode) Standard Brightness 80 Contrast 50 Colour Temp Warm RGB n/a Gamma 2.2

Acer XR341CK - Default Settings







Default Settings luminance (cd/m2) 263 Black Point (cd/m2) 0.24 Contrast Ratio 1096:1 Initially out of the box the screen was set in the default 'standard' eColor preset mode. You could tell the screen was using a standard gamut backlight and the image looked pretty good, but too bright for comfortable use. Colour balance felt good and the image quality was decent. We went ahead and measured the default state with the i1 Pro. The CIE diagram on the left of the image confirms that the monitors colour gamut (black triangle) is roughly equal to the sRGB colour space. There is some minor over-coverage, mostly in blue and green shades but not by anything significant. Default gamma was recorded at 2.0 average, leaving it with a 7% deviance from the target which was not too bad, but not great. The screen has 3 gamma modes available in the OSD and by default it was set to the supposed 2.2 gamma. We also tested the two other gamma modes for completeness and found the 1.8 mode returned a gamma average of 1.7 (23% out from our target), and the 2.4 mode delivered a 2.3 gamma average with 3% deviance from our target. We will look at that mode again in a moment as we felt it actually delivered a better picture out of the box in fact for day to day use. White point was measured at 6715k being slightly too cool from the target of 6500k but with a low 3% deviance. The screen was set in the default 'warm' colour temp mode incidentally. We again tested the other modes which returned the following colour temperature results: Colour Temperature Modes OSD option Measured white point Normal 7980k Cool 10,726k Blue Light 6129k User 6715k Warm (Default) 6715k The white point was probably best at the default 'warm' mode out of the box, and closest to our target of 6500k. The user mode is identical but does give you access to the RGB channels to calibrate the screen yourself. We will provide some recommended OSD setting adjustments in the following section to achieve a more accurate white point and default setup, even for those without a calibration tool available so you can try that too. Note that the low blue light mode also has another setting in the menu for levels of blue light reduction, defaulting to 70% when you enter that mode. There's also options for 50, 60 and 80% available. Luminance was recorded at a very bright 263 cd/m2 which is too high for prolonged general use. The screen was set at a default 80% brightness in the OSD menu but that is easy to change of course to reach a more comfortable setting without impacting any other aspect of the setup. The black depth was 0.24 cd/m2 at this default brightness setting, giving us a very good static contrast ratio (for an IPS-type panel) of 1096:1. Colour accuracy was moderate out of the box with a default dE average of 3.0, and a maximum of only 7.1. Testing the screen with various gradients showed fairly smooth transitions with no sign of any banding thankfully. There was some gradation evident as you will see from most monitors in darker tones. Overall the default setup was good, although some minor changes in the OSD can bring about some positive changes as reported in the following section.

Optimum OSD Adjustments Having tested the various settings and preset modes we thought it would be useful to summarise what we would consider to be the optimum OSD adjustments out of the box, before any calibration device is used to profile the screen. These are designed to help you reach a more comfortable and reliable setup without the need for a calibration tool. In the following section we will calibrate the screen properly and provide a calibrated ICC profile for those who would like to try it. Monitor OSD Option Recommended Optimum Settings eColor preset mode User Brightness 28 Contrast 50 Colour Temp User RGB Gain 55, 48, 48 Gamma 2.4

Acer XR341CK - Optimum OSD settings



Optimum OSD Settings luminance (cd/m2) 121 Black Point (cd/m2) 0.11 Contrast Ratio 1072:1 By changing any of the controls in the OSD you automatically move to the 'user' eColor preset mode anyway. We changed the gamma preset to 2.4 as we had already established that it was closest to our 2.2 gamma target. We also changed to the 'user' colour temp mode which allows us to change the RGB levels individually. By making the basic changes to the OSD menu as listed above we were able to improve the default setup quite nicely. We now had a slightly more accurate gamma, being measured at 2.2 average with a minor 2% deviance. White point was basically spot on to our target and the reduction in the brightness control delivered a more comfortable luminance, all the while maintaining a strong contrast ratio. The colour accuracy had also improved nicely, with 1.8 dE average now. Greys looked perhaps a little redder than we would like, but you can always turn the Red gain down a bit if you find that to be the case. Proper calibration as in the following section of course helps achieve even more accurate results. Calibration We used the X-rite i1 Pro spectrophotometer combined with the LaCie Blue Eye Pro software package to achieve these results and reports. An X-rite i1 Display Pro colorimeter was used to validate the black depth and contrast ratios due to lower end limitations of the i1 Pro device. Monitor OSD Option Calibrated OSD settings eColor preset mode User Brightness 28 Contrast 50 Colour Temp User RGB Gain 55, 48, 48 Gamma 2.4

Acer XR341CK - Calibrated Settings



Calibrated Settings luminance (cd/m2) 122 Black Point (cd/m2) 0.11 Contrast Ratio 1072:1 All the OSD changes from the previous section allowed us to obtain an optimum hardware starting point and setup before software level changes would be made at the graphics card level. We left the LaCie software to calibrate to "max" brightness which would just retain the luminance of whatever brightness we'd set the screen to, and would not in any way try and alter the luminance at the graphics card level, which can reduce contrast ratio. These adjustments before profiling the screen would help preserve tonal values and limit banding issues. After this we let the software carry out the LUT adjustments and create an ICC profile. Average gamma was now corrected to 2.2 average, correcting the 7% deviance we'd seen out of the box. There was still a minor 1% deviance measured but nothing major at all. The white point had already been corrected nicely in the previous section through adjustments to the OSD RGB levels. It was maintained at an accurate level, measured at 6529k (0% deviance), correcting the minor 3% default offset from before. Luminance had been improved thanks to the adjustment to the brightness control and was now being measured at 122 cd/m2. This left us a black depth of 0.11 cd/m2 and maintained an excellent static contrast ratio (for an IPS-type panel) of 1072:1. Colour accuracy of the resulting profile was excellent, with dE average of 0.4 and maximum of 1.0. LaCie would consider colour fidelity to be very good overall. Testing the screen with various colour gradients showed mostly smooth transitions. There was some gradation in darker tones but no banding evident thankfully. You can use our settings and try our calibrated ICC profile if you wish, which are available in our ICC profile database. Keep in mind that results will vary from one screen to another and from one computer / graphics card to another. Calibration Performance Comparisons

The comparisons made in this section try to give you a better view of how each screen performs, particularly out of the box which is what is going to matter to most consumers. When comparing the default factory settings for each monitor it is important to take into account several measurement areas - gamma, white point and colour accuracy. There's no point having a low dE colour accuracy figure if the gamma curve is way off for instance. A good factory calibration requires all 3 to be well set up. We have deliberately not included luminance in this comparison since this is normally far too high by default on every screen. However, that is very easily controlled through the brightness setting (on most screens) and should not impact the other areas being measured anyway. It is easy enough to obtain a suitable luminance for your working conditions and individual preferences, but a reliable factory setup in gamma, white point and colour accuracy is important and not as easy to change accurately without a calibration tool. From these comparisons we can also compare the calibrated colour accuracy, black depth and contrast ratio. After a calibration the gamma, white point and luminance should all be at their desired targets. Default setup of the screen out of the box was pretty good with the gamma being the only real issue with a 7% deviance and 2.0 average gamma measured. White point was slightly too cool but only by a minor 3% deviance, but contrast ratio was strong for an IPS panel. It's easy actually to obtain a better setup even without a calibration device if you follow our recommended OSD settings. That helps improve gamma and correct the white point also so it's easy to sort that if you want to. The display was strong when it came to black depth and contrast ratio for an IPS-type panel. With a calibrated contrast ratio of 1072:1 it was comparable to some of the better screens using this kind of panel technology. It was not quite as high as the recently tested Dell U2515H (1138:1) which holds the record for an IPS contrast ratio. It was very similar to the Dell U3415W (1091:1) as you might expect given they use the exact same panel. The similar, but flat format LG 34UM95 was close as well at 1064:1. Of course none of these IPS screens can compete with VA panel types which can reach over 2000:1 easily like the 32" BenQ BL3200PT, and even close to 5000:1 in the case of the Eizo FG2421. Check Pricing and Buy - Direct Links Amazon USA | Amazon UK | Amazon GER | Amazon CAN TFTCentral is a participant in the Amazon Services LLC Associates Programme, an affiliate advertising programme designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com, Amazon.co.uk, Amazon.de, Amazon.ca and other Amazon stores worldwide. We also participate in a similar scheme for Overclockers.co.uk.

Viewing Angles

Above: Viewing angles shown from front and side, and from above and below. Click for larger image Viewing angles of the XR341CK were very good as you would expect from an IPS panel. Horizontally there was very little colour tone shift until wide angles past about 45°. A slight darkening of the image occurred horizontally from wider angles as you can see above as the contrast shifted slighting. Contrast shifts were slightly more noticeable in the vertical field but overall they were very good. The screen offered the wide viewing angles of IPS technology and was free from the restrictive fields of view of TN Film panels, especially in the vertical plane. It was also free of the off-centre contrast shift you see from VA panels and a lot of the quite obvious gamma and colour tone shift you see from some of the modern VA panel type offerings. All as expected really from a modern IPS panel.

Above: View of an all black screen from the side. Click for larger version On a black image there is a characteristic white glow when viewed from an angle, commonly referred to as "IPS-glow". This is common on most modern IPS-type panels and can be distracting to some users. If you view dark content from a normal head-on viewing position, you can actually see this glow as your eyes look towards the edges of the screen. Because of the sheer horizontal size of this 34" panel, the glow towards the edges is more obvious than on small screens, where there isn't such a long distance from your central position to the edges. Some people may find this problematic if they are working with a lot of dark content or solid colour patterns. In normal day to day uses, office work, movies and games you couldn't really notice this unless you were viewing darker content. If you move your viewing position back, which is probably likely for movies and games, the effect reduces as you do not have such an extreme angle from your eye position to the screen edges. The glow effect was a little less than on flat 34" ultra-wide screens as the curved nature created a smaller angle between your eyes and the edges of the screen.



Panel Uniformity We wanted to test here how uniform the brightness was across the screen, as well as identify any leakage from the backlight in dark lighting conditions. Measurements of the luminance were taken at 36 points across the panel on a pure white background. The measurements for luminance were taken using BasICColor's calibration software package, combined with an X-rite i1 Display Pro colorimeter with a central point on the screen calibrated to 120 cd/m2. The below uniformity diagram shows the difference, as a percentage, between the measurement recorded at each point on the screen, as compared with the central reference point. It is worth noting that panel uniformity can vary from one screen to another, and can depend on manufacturing lines, screen transport and other local factors. This is only a guide of the uniformity of the sample screen we have for review.



Uniformity of Luminance

The luminance uniformity of the screen was moderate. T he screen seemed to be darker towards the top two corners where it dropped down by a maximum of 29% to 93 d/m2. The central and lower middle portions of the screen were within a smaller variation from the centrally calibrated point though, but in a couple of places the luminance did jump up a bit to 127 d/m2 maximum. Two thirds of the screen was within a 10% deviance from the centrally calibrated point.

Backlight Leakage



Above: All black screen in a darkened room. Click for larger version As usual we also tested the screen with an all black image and in a darkened room. A camera was used to capture the result. The camera showed there was some clouding detected along the upper left hand edge. It was not too bad though, but you could see it with the naked eye if viewing dark content in a dark room. Nevertheless it should not present any major problems in normal use.

General and Office Applications One of the key selling points of ultra-wide screens like the this is it's high resolution and large screen size. The 3440 x 1440 display offers a sharp but comfortable picture. Its pixel area is about 1.8 times larger than an Ultra-Wide Full HD 21:9 monitor, and about 2.4 times larger than a Full HD 16:9 monitor. It provides an efficient environment in using Microsoft Office programs showing 47 columns and 63 rows in excel. Thankfully the high resolution is of a very comfortable size on the 34" panel, with a 0.2325mm pixel pitch is is very comparable to a 27" 2560 x 1440 monitor (0.2331mm). This means you are basically getting a wider desktop to work with, with a similar font size to a 27" model, and maintaining the same vertical resolution as well. If you're coming from a lower resolution / larger pixel pitch you may still find the fonts look quite small to start with, but like the 27" 1440p models out there you soon get used to it. Side by side multi-tasking on this screen is excellent and you really do have a nice wide area to work with. We liked the curved format of the display actually for day to day office work. It just felt a bit more comfortable than a flat screen on a model as wide as this, bringing the corners a bit nearer to you. You didn't really notice the curve in normal use but we liked the feel. Probably down to user taste, so if in doubt try and see one in person. The light AG coating of the IPS panel doesn't produce any graininess to the image like some aggressive AG solutions can and so white office backgrounds look clean and clear. The wide viewing angles of the IPS panel technology provide stable images from different angles, meaning you can use the screen if you want for colour critical work, photos etc. It might be orientated at gamers, but it's IPS panel can deliver strong performance in other areas as well making it a good all-rounder. This panel technology still offers the widest viewing angles and so is well-suited to colour work. Some contrast shifts and IPS-glow may be evident because of the very wide size of the display, as you glance towards the edges from a centrally aligned position. That's hard to avoid on such a large desktop monitor from close up, even with IPS technology. The default setup of the screen was pretty good, and easy to tweak through the OSD to get an even better performance. We were also pleased with the strong 1072:1 contrast ratio (after calibration) as well. The brightness range of the screen was also very good, with the ability to offer a luminance between 310 and 41 cd/m2. This should mean the screen is perfectly useable in a wide variety of ambient light conditions, including darkened rooms. A setting of ~28 in the OSD brightness control should return you a luminance close to 120 cd/m2 out of the box. On another positive note, the brightness regulation is controlled without the need for the use of the now infamous Pulse-Width Modulation (PWM), and so those who suffer from eye fatigue or headaches associated with flickering backlights need not worry. There was some audible noise and whining from the screen at lower brightness settings, as you went below 40. It was not overly distracting but might bother those with silent systems. The screen also remains fairly cool even during prolonged use. There is no specific preset mode for office work or reading so you will have to set the user mode how you want. If you need different settings for gaming you can save up to 3 user defined gaming modes as well which is very handy. With the use of FreeSync instead of G-sync, the screen can offer a good range of connectivity options making it flexible for a lot of systems thankfully. Picture in Picture and Picture by Picture can be handy on a screen this size if you want to connect multiple devices as well, and that's a feature also only provided on this FreeSync version of the screen - not on the forthcoming G-sync Predator X34 model. The screen offers 4x USB 3.0 ports which can be useful and it was nice to keep this up to date with the modern version. Two also offer charging support but both are located on the back of the display so are not easy-access really. Integrated speakers can provide sound for the odd YouTube clip or mp3 if you want. There are no further extras like ambient light sensors or card readers which can be useful in office environments. Remember, this is aimed at gamers really. There was a reasonable range of ergonomic adjustments available from the stand allowing you to obtain a comfortable position for a wide variety of angles. They were mostly stiff though so you might not want to move it around too often. We did miss swivel a bit though. The VESA mounting support may also be useful to some people as well for more flexibility.

Above: photo of text at 3440 x 1440 (top) and 2560 x 1080 (bottom) The screen is designed to run at its native resolution of 3440 x 1440 and at a 75Hz recommended refresh rate. However, if you want you are able to run the screen outside of this resolution. We tested the screen at a lower 2560 x 1080 resolution to see how the screen handles the interpolation of the resolution, while maintaining the same aspect ratio of 21:9. At native resolution the text was very sharp and clear. When running at a 1080p resolution the text is still reasonably clear, with moderate levels of blurring. You do lose a lot of screen real-estate as well of course but the image seems to be quite well interpolated if needed.

Gaming Introduction The Acer XR341CK is a gamer-orientated screen, pairing an ultra-wide format curved display with a couple of gaming enhancements to deliver an interesting option for gamers. Firstly we should consider the format of the screen, with the 34" area offering a nice immersive experience and the wide 21:9 aspect proving popular for many gamers since it was introduced. It's nice also that the screen offers the full 3440 x 1440 resolution currently available on models this size, as opposed to the more limited 2560 x 1080 some 34" models have. The slight curve also adds to immersion feeling in games and we prefer it to flat 34" ultra-wide models. At the moment the 34" monitor space is a little limited by the panels being manufactured. At the moment only LG.Display and Samsung seem to be investing in this format, with nothing reported in the roadmaps for other main manufacturers like AU Optronics or Innolux. There's really only the choice for display manufacturers between LG.Display's IPS, and Samsung SVA panels. That's not necessarily a bad thing as IPS is always very popular with buyers and using an IPS panel like Acer have here, does allow them to offer a screen suitable for a wide range of uses, not just exclusively for gaming. There are no TN Film panels in this size and format at the moment so the IPS option is about as good as you can get at the moment for gaming needs. Unfortunately, IPS is somewhat limited in what it can offer. This isn't a fault of Acer's, they are only working with what panels they have available to them and making the most of them. IPS technology (and Samsung SVA for that matter) is still fairly limited when it comes to pixel response times. It can't compete with the speed of TN Film panels, and as yet LG.Display haven't found a way to drive response times lower like AU Optronics have with their recent high refresh rate AHVA (IPS-type) panels in the 27" space. Still, people have been using IPS for many years for gaming so there's no reason to think that a screen like this couldn't be used as long as the response times are handled right. We will look at that in the next section. Sure, they won't be quite as fast as TN Film panels, but they are still fine for many users. The availability of TN Film panels in this format would have given Acer more choice perhaps, and the ability to offer an even better gaming experience. Although we expect people would only then moan about the restrictions of TN Film for other uses. This leads us on to refresh rate. Again Acer are limited here by what is available panel-wise. LG.Display have yet to release any high refresh rate (144Hz) IPS panel in any size. They have a 27" 1080p panel expected in Q3 at some point but that's their first venture into that space. Response times are likely to be the limiting factor in their quest, as they need to be able to reliably drive them under 6.94ms average (without loads of overshoot) to make 144Hz viable. We will see what they manage when they finally release a high refresh panel later in the year - assuming a display manufacturer picks it up. That aside, an even bigger problem is that the 3440 x 1440 resolution offered on a screen this size is too high to run at 144Hz with current DisplayPort standards. We would need to see DisplayPort 1.3 for that kind of bandwidth to be viable. All in all, it's likely to be a fair amount of time before we see a 144Hz capable 3440 x 1440 screen sadly. In the mean time, Acer have done what they can with the available panel, within the confines of what it will support from a refresh rate point of view. This screen has been bumped up from the normal 60Hz to 75Hz. It's not a huge increase although it is a 25% improvement if you think about it. The screen has also been paired with AMD's FreeSync technology and so this higher refresh rate allows a wider dynamic refresh rate range to be used. 30 to 75Hz is available which is a decent range, and to be honest most of the FreeSync benefits would be realised within that range anyway. If you've got a powerful enough graphics card to output >75fps at 3440 x 1440 res then you can just set vsync to off for frequencies outside of the supported range and live with a bit of tearing, while delivering higher frame rates to the display. Sure, we would have liked to see the screen as 100Hz (as rumoured originally) or higher, but it's just not available at the moment. Although it's possible the forthcoming Predator X34 could be 100Hz we think it is very unlikely so don't hold your breath. Sadly one thing which is missing from the XR341CK is a Blur Reduction mode. The forthcoming Predator X34 G-sync version of the screen is expected to feature an ULMB blur reduction mode as part of the NVIDIA G-sync module, but that is not something included by default with FreeSync support so is missing from this model. Ultra Wide screen format IPS-type panel technology Max refresh rate support 75Hz FreeSync support Blur Reduction mode NVIDIA 3D Vision To make the most of this screen you will want to have a suitable AMD graphics card which supports Adaptive Sync/FreeSync. That will allow you to use one of the most interesting new features of this screen. One of the key selling points of FreeSync is that unlike G-sync it does not add a massive cost overhead to the display, and so actually even if you don't have a suitable graphics card to use FreeSync you can still benefit from everything else this screen has to offer. It should be noted that the screen can also be used from NVIDIA graphics cards without issue, and there's a good range of connectivity options provided to suit whatever card you've got. Again, you won't be able to use FreeSync, but everything else should work fine. This is therefore an attractive solution even if you don't intend to use FreeSync since it still provides a 75Hz capable IPS panel for gaming in a wide format, with some extras thrown in to enhance your experience.



Responsiveness and Gaming Quoted G2G Response Time 4ms G2G Quoted ISO Response Time n/a Panel Manufacturer and Technology LG.Display AH-IPS Panel Part LM340UW2-SSA1 Overdrive Used Yes Overdrive Control Available to User OD Mode Overdrive Settings Off, Normal, Extreme The XR341CK is rated by Acer as having a 4ms G2G response time, which indicates the panel uses overdrive / response time compensation (RTC) technology to boost pixel transitions across grey to grey changes. There is user control over the overdrive impulse within the OSD menu using the 'OD Mode' (overdrive) option. The part being used is the LG.Display AH-IPS LM340UW2-SSA1 panel, the exact same panel as already used in the Dell U3415W display. Have a read about response time in our specs section if you need additional information about this measurement. We will first test the screen using our thorough response time testing method. This uses an oscilloscope and photosensor to measure the pixel response times across a series of different transitions, in the full range from 0 (black) to 255 (white). This will give us a realistic view of how the monitor performs in real life, as opposed to being reliant only on a manufacturers spec. We can work out the response times for changing between many different shades, calculate the maximum, minimum and average grey to grey (G2G) response times, and provide an evaluation of any overshoot present on the monitor. We use an ETC M526 oscilloscope for these measurements along with a custom photosensor device. Have a read of our response time measurement article for a full explanation of the testing methodology and reported data. AMD kindly sent us a Club 3D Radeon R9 290 Series for testing as well:

Response Time Setting Comparison

The XR341CK comes with a user control for the overdrive impulse available within the OSD menu in the 'setting' section, as well as via one of the quick launch options shown above. There are 3 options available here under the OD Mode setting. First of all we carried out a smaller sample set of measurements in all 3 of the OD Mode settings. These, along with various motion tests allowed us to quickly identify which was the optimum overdrive setting for this screen. You will see that we have tested the response time behaviour on both an NVIDIA and an AMD graphics card. We did this as we know that FreeSync systems have caused some odd behaviour on other displays in the past, including making the overdrive impulse not work at all. You will see from the tests below that there's another odd behaviour here. Firstly we tested the response times with OD set to off, effectively turning off the overdrive impulse. Response time and overshoot levels were very similar from both the NVIDIA and AMD FreeSync graphics card. The average response time was measured at 11.9ms - 12.5 G2G average which was actually not that slow, but certainly not optimum for this technology. Rise times were a bit slower than fall times and there was some obvious blurring to moving images. There was no overshoot in this mode since OD was turned off, but we would hope for better responsiveness from the other modes. Here's where the odd behaviour starts as it seems the AMD FreeSync system causes some different behaviour to the overdrive circuit in the monitor. On some early release FreeSync screens we saw that when connected to a FreeSync system (FreeSync card + compatible driver + DP connection) it caused the overdrive circuit to be turned off completely. This happened on the BenQ XL2730Z and Acer XG270HU and the manufacturers both had to introduce a firmware update to fix it, allowing for the overdrive circuit to function again when using a FreeSync system. A graphics card driver was also released by AMD as part of the fix. On the Acer XR341CK the overdrive function does work when connected to a FreeSync system, but it behaves quite differently to when it's connected to an NVIDIA card or non FreeSync system (like an AMD card without FreeSync support, or even an AMD card with FreeSync but using HDMI instead of DP). From the NVIDIA test card moving up to OD mode up to the 'normal' mode brought about some, mostly positive changes. Response times had improved significantly, down to 7.9ms G2G average. Some of the particularly slow transitions from before had been sped up nicely, but those particular transitions now also showed some moderate to high levels of overshoot as a result, up to around 20% error. We would perhaps have preferred a slightly less aggressive overdrive impulse and lower overshoot, but it was not too severe. Certainly a preferred option over the 'off' setting. In fact when testing the OD normal mode from the AMD FreeSync system the screen behaves a little more how we would like. Response times were slightly slower at 8.6ms G2G, but there was no overshoot now at all. This was more on par with some of the best 60Hz IPS-type panels we've tested and we preferred this slightly more modest overdrive impulse and freedom from overshoot. This performance applies when using a FreeSync end to end system. If you use an AMD card without FreeSync, or break the FreeSync chain anywhere along the way (old driver, not using DP connection) then it will behave like the NVIDIA tests above.

NVIDIA / Non FreeSync system, OD set to Normal

Transition: 0-150-0 (scale = 20ms)

AMD FreeSync system, OD set to Normal

Transition: 0-150-0 (scale = 20ms) As an example you can see the graphs above for the 0-150-0 transition. The top graph is from the NVIDIA graphics card (or any non FreeSync system) and you can see some overshoot of 18% on the rise time where the graph peaks above the flat upper line. The bottom graph is from the AMD FreeSync system and shows no overshoot. The 'extreme' OD setting also behaved very differently from the NVIDIA system and AMD FreeSync system. The maximum 'extreme' OD setting pushed things too far on the NVIDIA card (or a non FreeSync system). There was only a minor improvement in response times here, with an average 7.0ms G2G measured. The overshoot was massive though here, and very obvious in practice as well. This mode should be avoided as a result from NVIDIA cards or non-FreeSync systems. The AMD FreeSync system behaved very similarly to the OD 'normal' mode, again with no overshoot at all. This 'extreme' setting didn't seem to affect the response times at all on the FreeSync system.

NVIDIA / Non FreeSync system, OD set to Extreme

Transition: 0-150-0 (scale = 20ms)

AMD FreeSync system, OD set to Extreme

Transition: 0-150-0 (scale = 20ms) As an example you can see the graphs above for the 0-150-0 transition. The top graph is from the NVIDIA graphics card (or any non FreeSync system) and you can see some massive overshoot of 108% on the rise time where the graph peaks above the flat upper line. The bottom graph is from the AMD FreeSync system and shows no overshoot. OD Setting Comparison Using PixPerAn Motion Tests





If we take some test photos using the PixPerAn tool you can make some further visual comparisons between the overdrive settings. You can also see how the NVIDIA / Non FreeSync system behaves as compared with a FreeSync system. On the NVIDIA card (or non FreeSync AMD system) the 'normal' OD mode is optimum, delivering smoother, sharper movement as compared with having the setting off. There is a less obvious blurring to the moving image. Some transitions we know show some moderate to high levels of overshoot but nothing too major and not actually picked out in the specific colour changes used here in the PixPerAn software. The 'extreme' mode pushes the overdrive impulse too far and some very noticeable dark and pale trailing is now evident. On the FreeSync system the story is different. There is no overshoot in any mode. The normal and extreme settings are basically the same and perform optimally. They offer response times only slightly slower than the 'normal' mode on an NVIDIA system, but with no overshoot evident at all. We observed the same thing in FreeSync motion demos like their Windmill demo tool. To summarise, if you're using a non FreeSync system of any sort, stick to OD normal. The responsiveness is good but you do have to live with some moderate levels of overshoot in places. If you have a FreeSync end to end system, use OD normal which is slightly slower but has no overshoot, and in our view offers a better performance balance than when using a non-FreeSync system.

More Detailed Measurements

OD Normal, FreeSync System Having established that the OD normal setting offered the best response/overshoot balance we carried out our normal wider range of measurements as shown below. Tests were completed from a FreeSync system since that is the target audience for this screen. The average G2G response time was more accurately measured at 8.7ms which was very good overall for an IPS-type panel. Transitions were fairly consistent across the board although changes to white (x > 255) and to black (x > 0) were a bit faster. No transitions reached down as low as the advertised 4ms G2G, but that's not really a surprise. Overall this was a good performance for a normal refresh rate ((60 - 75Hz range) IPS panel at the moment. There was basically no overshoot at all on any transition as long as you were using a FreeSync end to end system. If you don't have a FreeSync system then the response time behaviour is a little different, with moderate to high levels of overshoot detected on some transitions at this 'normal' OD setting. See the previous section of this review for more info.



144Hz Frame Skipping Bug from NVIDIA card? We found that from our NVIDIA test system when running at the full 3440 x 1440 resolution and 75Hz refresh rate, that the screen seemed to drop some frames. We verified this via the tests at BlurBusters.com, but you could also see the issue with the naked eye on moving content like PixPerAn. In those tests the image skipped and jumped a bit. It only did this at the maximum 75Hz refresh rate, not at anything lower like 60Hz. We found no such issue with the screen from our AMD system, either using a proper FreeSync end to end setup, or breaking the FreeSync chain and using the card with an older driver or without DisplayPort. Perhaps this is an issue with NVIDIA cards. We've reported it back to Acer for further checks.





Display Comparisons The above comparison table and graph shows you the lowest, average and highest G2G response time measurement for each screen we have tested with our oscilloscope system. There is also a colour coded mark next to each screen in the table to indicate the RTC overshoot error, as the response time figure alone doesn't tell the whole story. Assuming you have the screen connected to a FreeSync end to end system the response time performance of the XR341CK was pretty much on par with the best normal refresh rate IPS-type panels we've seen to date. At best it seems response times can be driven down to around 8.5ms G2G while still being free from distracting overshoot issues. Here on the XR341CK Acer had achieved 8.7ms G2G which was pleasing. The high refresh 144Hz IPS-type panels used in the Acer XB270HU and Asus MG279Q can achieve lower response times, down to ~5.5ms G2G and without overshoot being an issue in the best cases. Here, the panel is a normal refresh rate panel, albeit pushed up a little from 60Hz to 75Hz. Response times were better than we'd seen from the Dell U3415W using the same panel (10.6ms G2G, some low overshoot) which was pleasing. Fast TN Film panels can reach even lower than all these IPS-type panels of course, down to 2.9ms G2G in the case of the Asus ROG Swift PG278Q, although with some moderate levels of overshoot as a result. The screen was also tested using the chase test in PixPerAn for the following display comparisons. As a reminder, a series of pictures are taken on the highest shutter speed and compared, with the best case example shown on the left, and worst case example on the right. This should only be used as a rough guide to comparative responsiveness but is handy for a comparison between different screens and technologies as well as a means to compare those screens we tested before the introduction of our oscilloscope method.

34" 4ms G2G LG.Display AH-IPS @ 75Hz (OD = Normal) In practice the Acer XR341CK performed best with OD at normal. From a FreeSync system there were low levels of blurring evident and no overshoot at all. From a non-FreeSync system (inc NVIDIA cards) the blurring was ever so slightly less, but some transitions showed moderate to high levels of overshoot as we've seen from our oscilloscope measurements.

34" 4ms G2G LG.Display AH-IPS @ 75Hz (OD = Normal)

34" 8ms G2G LG.Display AH-IPS (Response Time = Normal)

34" 5ms G2G LG.Display AH-IPS (Response Time = Middle) The above images show a comparison with the two other 34" ultra-wide screens we've tested. The Dell U3415W featured the exact same panel as the Acer but was slightly slower in practice we felt. Our oscilloscope measurements also confirmed slightly slower response times on the Dell, and some low levels of overshoot which the Acer did not have. The LG was pretty similar to them both as well although slightly slower again than the Acer. Not really much to separate the three screens here to be honest. The Acer does have a higher refresh rate at 75Hz though, whereas the other two are 60Hz.



34" 4ms G2G LG.Display AH-IPS (OD = Normal)

27 " 4ms G2G AU Optronics AHVA (IPS-type) @ 144Hz (OD = Normal)

27 " 1ms G2G AU Optronics TN Film @ 144Hz (OD = Normal)

27 " 1ms G2G AU Optronics TN Film @ 144Hz (AMA = High)

23.5" 4ms G2G Sharp MVA + 120Hz We've also included a comparison above against some other very fast 120Hz+ compatible screens we have tested. The screens shown here are all aimed primarily at gamers and have various features and extras which make them more suitable overall for gaming. Firstly there is a comparison against the excellent Acer XB270HU with very fast response times (5.5ms G2G, no overshoot), 144Hz refresh rate and also NVIDIA G-sync and Ultra Low Motion Blur (ULMB) support. It's currently our bench-mark for IPS panel gaming - well, actually our current favourite gaming screen of any type! Then there's the very popular Asus ROG Swift PG278Q with its 144Hz refresh rate and fast response time TN Film panel. This showed very fast pixel response times (2.9ms G2G), with moderate levels of overshoot, but smooth movement thanks to its increased refresh rate. You are able to reduce the motion blur even more through the use of the ULMB strobed backlight as well if you need to and again this model also supports NVIDIA's G-sync technology. Then there is a comparison against the BenQ XL2730Z with another very fast TN Film panel and 144Hz refresh rate. This showed very low levels of motion blur (3.4ms G2G), but some dark overshoot was introduced as a side-effect as you can see. This screen also includes a native Blur Reduction mode to help eliminate further perceived motion blur and works well, along with AMD FreeSync support. Lastly there is the MVA based Eizo FG2421 screen with a fast response time (especially for the panel technology being used) and 120Hz refresh rate support. There is also an additional 'Turbo 240' motion blur reduction mode which really helps reduce the perceived motion blur in practice.



FreeSync Please have a read of our detailed article which talks more about variable refresh rate technologies including FreeSync. We won't go in to detail about it here but will talk a bit about its operation on the XR341CK specifically. The FreeSync range supported on this screen is 30 - 75Hz. Sadly the screen cannot support higher refresh rates for reasons we've discussed earlier. The real benefits of adaptive refresh rates comes at the lower ends anyway, typically between 40 and 70 Hz. The lower limit of 30Hz gives you a bit more room to play with here. If you do output more than 75fps then you have the choice as to whether the screen behaves as if Vsync is on or off, outside of FreeSync range. Tearing tends to be less problematic at higher refresh rates anyway so you could well have FreeSync operation between 30 and 75Hz, and then have Vsync off for anything above, in case you can output more than 75 fps regularly. That in itself is a fair challenge on a screen with this resolution. We've already discussed the difference in response time behaviour when connected to a FreeSync system (end to end with compatible card, driver and DP connection), and when connected to a non-FreeSync system (inc NVIDIA cards). The screen is best when connected to a FreeSync system we felt, with a freedom from any overshoot being a key advantage. Obviously you then also get to use the actual FreeSync feature which is very useful.

144Hz Frame Skipping Bug from NVIDIA card? We found that from our NVIDIA test system when running at the full 3440 x 1440 resolution and 75Hz refresh rate, that the screen seemed to drop some frames. We verified this via the tests at BlurBusters.com, but you could also see the issue with the naked eye on moving content like PixPerAn. In those tests the image skipped and jumped a bit. It only did this at the maximum 75Hz refresh rate, not at anything lower like 60Hz. We found no such issue with the screen from our AMD system, either using a proper FreeSync end to end setup, or breaking the FreeSync chain and using the card with an older driver or without DisplayPort. Perhaps this is an issue with NVIDIA cards. We've reported it back to Acer for further checks.





Additional Gaming Features Aspect Ratio Control - The XR341CK has 3 options for aspect ratio control through the OSD 'setting' section menu, using the 'wide mode' option as shown above. There are options for full, aspect, and 1:1 pixel mapping which is good to see. Given the unusual 21:9 aspect ratio of the screen it's good to have other options available so it can handle 16:9, 5:4 and 4:3 inputs properly. Note that NVIDIA G-sync screens at this time are not provided with an internal scaler, and so having these options available here is an advantage of using AMD FreeSync instead. Preset Modes - There are 3 game modes which you can customise and save you like, which allows you to set the screen up for different applications. You can use these for other uses as well of course if you wanted to.





Lag We have written an in depth article about input lag and the various measurement techniques which are used to evaluate this aspect of a display. It's important to first of all understand the different methods available and also what this lag means to you as an end-user. Input Lag vs. Display Lag vs. Signal Processing To avoid confusion with different terminology we will refer to this section of our reviews as just "lag" from now on, as there are a few different aspects to consider, and different interpretations of the term "input lag". We will consider the following points here as much as possible. The overall "display lag" is the first, that being the delay between the image being shown on the TFT display and that being shown on a CRT. This is what many people will know as input lag and originally was the measure made to explain why the image is a little behind when using a CRT. The older stopwatch based methods were the common way to measure this in the past, but through advanced studies have been shown to be quite inaccurate. As a result, more advanced tools like SMTT provide a method to measure that delay between a TFT and CRT while removing the inaccuracies of older stopwatch methods. In reality that lag / delay is caused by a combination of two things - the signal processing delay caused by the TFT electronics / scaler, and the response time of the pixels themselves. Most "input lag" measurements over the years have always been based on the overall display lag (signal processing + response time) and indeed the SMTT tool is based on this visual difference between a CRT and TFT and so measures the overall display lag. In practice the signal processing is the element which gives the feel of lag to the user, and the response time of course can impact blurring, and overall image quality in moving scenes. As people become more aware of lag as a possible issue, we are of course keen to try and understand the split between the two as much as possible to give a complete picture. The signal processing element within that is quite hard to identify without extremely high end equipment and very complicated methods. In fact the studies by Thomas Thiemann which really kicked this whole thing off were based on equipment worth >100,1000 Euro, requiring extremely high bandwidths and very complicated methods to trigger the correct behaviour and accurately measure the signal processing on its own. Other techniques which are being used since are not conducted by Thomas (he is a freelance writer) or based on this equipment or technique, and may also be subject to other errors or inaccuracies based on our conversations with him since. It's very hard as a result to produce a technique which will measure just the signal processing on its own unfortunately. Many measurement techniques are also not explained and so it is important to try and get a picture from various sources if possible to make an informed judgement about a display overall. For our tests we will continue to use the SMTT tool to measure the overall "display lag". From there we can use our oscilloscope system to measure the response time across a wide range of grey to grey (G2G) transitions as recorded in our response time tests. Since SMTT will not include the full response time within its measurements, after speaking with Thomas further about the situation we will subtract half of the average G2G response time from the total display lag. This should allow us to give a good estimation of how much of the overall lag is attributable to the signal processing element on its own. Lag Classification

To help in this section we will also introduce a broader classification system for these results to help categorise each screen as one of the following levels: Class 1) Less than 16ms / 1 frame lag at 60Hz - should be fine for gamers, even at high levels

Class 2) A lag of 16 - 32ms / One to two frames of lag at 60Hz - moderate lag but should be fine for many gamers. Caution advised for serious gaming and FPS

Class 3) A lag of more than 32ms / more than 2 frames of lag at 60Hz - Some noticeable lag in daily usage, not suitable for high end gaming For the full reviews of the models compared here and the dates they were written (and when screens were approximately released to the market), please see our full reviews index. (Measurements in ms) Normal Mode Low Latency Mode Total Display Lag (SMTT 2) 7.13 8.67 Pixel Response Time Element 4.35 4.35 Estimated Signal Processing Lag 2.78 4.32 Lag Classification 1 1 Class 1 We have provided a comparison above against other models we have tested to give an indication between screens. The screens tested are split into two measurements which are based on our overall display lag tests (using SMTT) and half the average G2G response time, as measured by the oscilloscope. The response time is split from the overall display lag and shown on the graph as the green bar. From there, the signal processing (red bar) can be provided as a good estimation. The screen features a 'low latency mode' option in the OSD menu as shown above. We measured the lag with and without this turned on. With the feature turned off there was a total lag of only 7.13ms measured. Approximately 4.35ms of that can be accounted for by pixel response times, leaving an estimated signal processing lag of only 2.78ms. Oddly, with the low latency mode turned on the measurement went up very slightly, to a total display lag of 8.67ms. We're not sure why this would be the case, but the lag is low enough with it turned off anyway. If for any reason you experience anything different try using that mode as well. The lag is very low and should mean the screen is perfectly fine for a wide variety of gaming needs, including first person shooters.



Movies and Video The following summarises the screens performance in video applications: 34" screen size makes it a good option for an all-in-one multimedia screen, and pushing towards the diagonal size of a lot of smaller end LCD TV's even.

21:9 aspect ratio is well suited to videos and particularly movies, leaving smaller borders on DVD's and wide screen content at the top and bottom. The ultra-wide aspect and size is well-suited to watching movies and really works well.

3440 x 1440 resolution can support full 1080 HD resolution content.

Digital interfaces support HDCP for any encrypted and protected content

HDMI, HDMI 2.0, MHL and DisplayPort connections available. Nice to see HDMI connectivity included for modern DVD players, Blu-ray, consoles etc.

Cables provided in the box for HDMI and DisplayPort.

Light AG coating provides clear images with no major graininess, and without the unwanted reflections of a glossy solution.

Wide brightness range adjustment possible from the display, including high maximum luminance of ~310 cd/m 2 and a good minimum luminance of 41 cd/m 2 . This should afford you very good control for different lighting conditions. Contrast ratio remains stable across most of that adjustment range as well and is excellent for an IPS-type panel at >1000:1. Brightness regulation is controlled without the need for PWM and so is flicker free at all settings which is pleasing.

Black depth and contrast ratio are excellent for an IPS-type panel at 1072:1 after calibration. Detail in darker scenes should not be lost as a result.

There is a specific 'movie' eColor preset mode available for movies or video in the OSD which is basically just preset brightness level. You might be better setting up the screen to your liking and saving it then as one of the 3 user defined game modes.

Good pixel responsiveness which can handle fast moving scenes in movies without issue. No real overshoot issues which is good news if using a FreeSync system. If you're using another non-FreeSync system there's some moderate overshoot in places on the screen. Just stick to the 'Normal' Response Time setting for optimum performance whichever way you go.

Wide viewing angles from IPS panel technology meaning several people could view the screen at once comfortable and from a whole host of different angles. White IPS glow from an angle may be an issue for some darker content.

Some slight areas of backlight leakage but nothing major on our sample which is good. Some uniformity variations may be visible on darker movie scenes in darkened room conditions.

Pretty good range range of ergonomic adjustments available from the stand, making it fairly easy to position the screen in different ways for viewing from different positions. They were stiff to move and the screen is heavy, so you won't want to move it around too often. The lack of side to side swivel was a bit of a shame though.

Integrated 2x 7W DTS sound stereo speakers offered on this model, may be ok for the odd video clip but probably not for any movie viewing.

Decent range of hardware aspect ratio options available which is very useful for external devices considering the unusual 21:9 aspect ratio here.

Picture By Picture (PbP) and Picture In Picture (PiP) are available on this model.





Conclusion We know how excited people were to get a detailed review of this monitor as quickly as possible, so we decided to release this as a full review straight away. We worked overtime to bring you this quickly as well so if you appreciate the early access to the review and enjoy reading and like our work, we would welcome a donation to the site to help us continue to make quality and detailed reviews for you. We found the XR341CK an interesting and fun screen to test. Clearly it's aimed at gamers and in this 34" ultra-wide space it offered some obvious improvements over what was already in the market. You get the high resolution, large screen size, ultra-wide aspect ratio, curved screen format and all round performance from the IPS panel that people have been attracted to before now. Acer have done a nice job squeezing some additional performance out of the panel as best they can, within the confines of what is currently available from panel manufacturers. The addition of FreeSync is obviously a big bonus, especially considering the demands on your graphics card from a screen of this resolution. Response times have been improved a little compared with the other 34" ultra-wide screens we've tested so far, and no overshoot was present either (assuming you're using a FreeSync system). Lag was also very low, there were some handy gaming extras like the game modes, and even the pretty cool ambient light system. Sure, it can't keep up with some of the new 27" IPS-type panels with their 144Hz refresh rate, blur reduction modes and faster response times. But it's still a nice gaming option in this sector. We noticed an issue with the screen from NVIDIA cards, and so we would recommend the screen mainly for AMD FreeSync users - which is the target audience. There's an NVIDIA G-sync version coming later on which is more suitable for NVIDIA users anyway. In other areas the IPS panel offered some strong all round performance. Default setup was reasonable, and easy to adjust and improve through the comprehensive OSD menu. Contrast ratio was strong for an IPS panel and the light AG coating and flicker free backlight are always welcome. The connectivity options were good and there were a nice set of extras like speakers and USB 3.0 ports offered. The stand was a little limited, both in function and design. You need a deep desk to accommodate the deep three pronged stand shape, and the adjustments were stiff and missing swivel as well. The OSD had lots of options but was a bit fiddly to use and annoying to navigate through on occasion. Perhaps the main limitation of IPS panels now remains the pale IPS-glow you see on darker content, something accentuated by the large and wide screen size here. If you want a 34" screen for gaming then this is the best of the bunch at the moment. We also look forward to seeing what the Predator X34 can offer NVIDIA users when it's launched.

Pros Cons Good response times for IPS and very low lag Stand a little limited in design and function FreeSync included, without stopping the overdrive circuit from working IPS glow may be a problem on a screen this size and shape Good all round performance from IPS panel Frame skipping bug on NVIDIA cards at the moment? Check Pricing and Buy - Direct Links Amazon USA | Amazon UK | Amazon GER | Amazon CAN TFTCentral is a participant in the Amazon Services LLC Associates Programme, an affiliate advertising programme designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com, Amazon.co.uk, Amazon.de, Amazon.ca and other Amazon stores worldwide. We also participate in a similar scheme for Overclockers.co.uk.