Author: Adam Simmons

Date published: October 15th 2019



Many gamers are comfortable with a screen size of around 24” and are seeking an affordable solution with a good mixture of image quality and responsiveness. So far the high refresh rate options have centred around either TN models, built for speed, or VA models offering strong contrast and some improvements in colour handling at the expense of responsiveness. The AOC C24G1 is a good example of a VA model that offered a nice mixture of image quality and responsiveness. The AOC 24G2U (referred to as 24G2U/BK due to black plastic, or simply 24G2 in some regions) offers an alternative with IPS-type panel. It isn’t designed to replace the C24G1, comparing IPS and VA panel types is a bit of an apples to oranges comparison. But some notable changes aside from just panel type include a more generous colour gamut and the use of a flat rather than curved screen. We test all of these features out and assess the performance of the monitor more generally, using out usual suite of ‘real-world’ tests.





The monitor uses a 23.8” IPS-type panel, more specifically the Panda LC238LF1F FFS (Fringe-Field Switching) IPS-type CELL with custom backlight. This supports a 144Hz refresh rate and 8-bit colour. A 1ms MPRT (Moving Picture Response Time) is specified, with the monitor using its strobe backlight setting. As usual, take such response times with a pinch of salt. Some of the key ‘talking points’ for this monitor have been highlighted in blue below, for your reading convenience.





Screen size: 23.8 inches

Panel type: TPV TPM238WF1 [Panda panel with custom backlight] FFS IPS (In-Plane Switching) type LCD

Native resolution: 1920 x 1080

Typical maximum brightness: 250 cd/m²

Colour support: 16.7 million (6-bits per subpixel plus dithering)

Response time (MPRT): 1ms

Refresh rate: 144Hz (variable, with Adaptive-Sync)

Weight: 2.95kg

Contrast ratio:1000:1

Viewing angle: 178º horizontal, 178º vertical

Power consumption: 21W (max)

Backlight: WLED (White Light Emitting Diode)

Typical price as reviewed: £180 ($350 USD)

The monitor adopts a homely style, with only a subtle hint of ‘gaming monitor’ look. Matte black plastics are used extensively, broken up by some dark metallic red plastic elements. We found these well-blended overall and not eye-catching when just using the monitor normally, less eye-catching than they appear in press photos. The stand base has an interesting design, with 2 longer front legs and 2 short rear legs. In some regions such as North America this is silver matte plastic rather than the black matte plastic shown in the image. The monitor adopts a 3-sided borderless design – or ‘dual-stage’ as the less misleading term we prefer to use. This includes a very slender panel border around the image, blending in seamlessly with the rest of the screen, plus a sleek black plastic outer component. Including both elements the bezels are a svelte ~4.5mm (0.18 inches) at the top and sides. The bottom bezel is thicker, ~18mm (0.71 inches) with just a sliver of panel border. The screen itself is naturally dominant from the front, with a medium matte anti-glare screen surface. We explore this later.





The OSD (On Screen Display) is controlled by pressable buttons beneath the right side of the bottom bezel. A small forwards-facing power LED is also included in this region, to the right of the buttons. This glows white when the monitor is on and amber when it enters a low power state (signal to the system is lost). The video below explores this menu system.





From the side the screen is quite svelte; ~10mm (0.39 inches) at thinnest point but lumping out towards the stand attachment point, centrally. The reasonably robust and fully adjustable can be seen from this angle. The stand offers the following adjustability; tilt (3.5° forwards, 21.5° backwards), height (130mm or 5.12 inches), swivel (30° left and 30° right) and pivot (90° clockwise rotation into portrait). At lowest stand height the screen clears the desk by ~60mm (2.36 inches), with the top of the screen ~380mm (14.96 inches) above the desk. The total depth of the monitor including stand is ~230mm (9.06 inches), with the screen sitting ~45mm (1.77 inches) back from the front edge of the stand. It’s therefore a fairly compact design, which will be welcomed by some users with less deep desks who still wish to keep a decent distance between the screen and their eyes.





The rear of the monitor is mainly matte black plastic, with some dark red satin-finish plastic elements. These include some red chevrons towards the sides, a vertical red stripe running down the centre of the stand neck and a red ring where the stand neck and base meet. A cable-tidy loop can be found towards the bottom of the stand neck. The included stand is attached with a quick-release mechanism and can be easily removed using by pressing the button beneath the port attachment point. This reveals 100 x 100mm VESA holes for alternative mounting. The monitor ‘U variant of the monitor includes 4 USB 3.0 ports (yellow coloured one supports fast charging) plus upstream, facing diagonally downwards. The remaining ports face downwards and include; 2 HDMI 1.4 ports, DP 1.2a, VGA, 3.5mm audio input, a 3.5mm headphone jack and AC power input (internal power converter). Beneath and slightly to the right of the port area there’s a K-Slot. The ‘U’ variant also includes 2 x 2W speakers, which provide basic and not particularly high-quality sound output.





The full capability of the monitor including the 1920 x 1080 resolution, 144Hz refresh rate and Adaptive-Sync can be leveraged via either HDMI or DP. Note that Nvidia users with compatible systems can only use Adaptive-Sync (‘G-SYNC Compatible Mode’) via DisplayPort. Standard accessories include a power cable, DP cable and HDMI cable. This may vary regionally.





The image below is a macro photograph taken on Notepad with ClearType disabled. The letters ‘PCM’ are typed out to help highlight any potential text rendering issues related to unusual subpixel structure, whilst the white space more clearly shows the actual subpixel layout alongside a rough indication of screen surface. This model employs a medium matte anti-glare screen surface with a fairly smooth surface texture. The screen surface offers good glare handling, whilst the fairly smooth surface texture prevents an obvious grainy look to lighter shades. There is just a light ‘misty’ graininess, no ‘smeary’ graininess nor a sandy appearance. This provides a somewhat smoother appearance to lighter shades than offered by competing TN models. The screen surface isn’t quite as ‘light’ or low haze as on competing VA models such as the C24G1.







As shown above, the monitor uses the standard RGB (Red, Green and Blue) stripe subpixel layout. This is the default expected by modern operating systems such as Microsoft Windows and Apple MacOS. You needn’t worry about text fringing from non-standard subpixel layouts as a Mac user and don’t need to run ClearType as a Windows user. You may still wish to run through the ClearType wizard and adjust according to preferences, however. The subpixel layout and arrangement is normal and we had no subpixel-related concerns related to sharpness or text clarity on this model.





The monitor includes a variety of ‘Game Mode’ image presets; ‘FPS’, ‘RTS’, ‘Racing’, ‘Gamer 1’, ‘Gamer 2’ and ‘Gamer 3’. These change various settings in the OSD and blocks off certain settings. Many also add a sharpness filter, over-sharpening the image with no way to disable this filter on that specific preset. They do nothing to improve input lag or monitor responsiveness, although different presets have different ‘Overdrive’ settings associated with them. The ‘FPS’, ‘RTS’ and ‘Racing’ presets lock off the ‘Luminance’ menu (brightness locked to a high level), ‘Color Setup’ menu and disable access to most of the ‘Game Setting’ menu (including ‘Overdrive’). The numbered ‘Gamer’ presets offer more flexibility and allow customisation of various settings, although the ‘Color Setup’ menu is still blocked off. We explore these briefly in the OSD video but for this section will be focusing on settings which we see as more practical and interesting.

The table below shows white point and gamma readings taken using a Datacolor SpyderX Elite colorimeter, using various OSD settings, alongside general observations on the image. Our test system runs Windows 10 and an Nvidia GTX 1080 Ti connected via the supplied DP cable. Additional testing was performed using an AMD Radeon RX 580 and using HDMI, although observations for this table didn’t vary significantly between GPUs or inputs. No additional monitor drivers or ICC profiles were specifically loaded for testing purposes and the monitor was left to run for over 2 hours before observations and readings were taken for the below table. Aside from for our ‘Test Settings’, where various adjustments were made, assume factory defaults were used. The refresh rate was set to 144Hz in Windows, although this didn’t significantly affect the values or observations on this table. When viewing the figures in this table, note that for most PC users ‘6500K’ for white point and ‘2.2’ for gamma are good targets to aim for. Individual targets depend on individual uses, tastes and the lighting environment, however.

Finally, note that Nvidia GPU users will see two separate lists of refresh rates in Nvidia Control Panel. The first list (‘Ultra HD, HD, SD’) will be used by default with the ‘1080p, 1920 x 1080 (native)’ option. The highest refresh rate listed there will be 120Hz. If you scroll down you’ll see another list, ‘PC’. If you select ‘1920 x 1080’ in that list you’ll have access to additional refresh rates, including 144Hz. Also be aware that some refresh rate options (in the first list) will default to using a limited range RGB signal which will greatly affect the image when using HDMI; refer to this article for information on correcting the issue.

Straight from the box the monitor provided a fairly bright, vibrant and varied image. Aside from a slight green tint, things were quite well-balanced. Gamma tracking was appropriate for the ‘2.2’ curve, with a few alternative settings available if users wish to adjust this according to preferences. The image below shows the gamma curve under our ‘Test Settings’, making fairly minor adjustments compared to the factory defaults. Things track rather close to the desired ‘2.2’ curve. Given the intended uses of the monitor, inter-unit variation and pleasing performance following OSD tweaking alone we will not be providing any ICC profiles for this model or using them in the review.



Gamma 'Test Settings' The monitor also includes some ‘LowBlue Mode’ Low Blue Light (LBL) settings, accessible in the ‘Game Setting’ section of the OSD. It would’ve been nice if these could be quickly cycled or enabled and disabled without entering the main menu, but they’re still quite easy to access. The ‘Reading’ mode was particularly effective, significantly reducing blue light output. Reducing exposure to blue light is particularly important in the hours leading up to sleep as blue light affects sleep hormones. Increasing alertness and making it more difficult for the body to shut off. These settings retain a relatively strong green channel, as this maximises contrast compared to reducing this significantly alongside the blue channel. The overall balance was better than some LBL settings we’ve tried and we found our eyes adjusted to the tint quite well in time. We used this setting for our own viewing pleasure in the evenings, although not for specific testing beyond that involving this particular setting.



Test Settings For our ‘Test Settings’ we reduced brightness and adjusted the colour channels. It’s important to bear in mind that individual units and preferences vary, so these settings are just a suggestion and won’t be optimal in all cases. Assume any setting not mentioned, including ‘Contrast’, was left at default. We’ve also included the refresh rate used in Windows and the preferred ‘Overdrive’ setting used for most of the review, just for reference.





Brightness= 35 (according to preferences and lighting) Brightness= 35 (according to preferences and lighting) Color Temp. = User R= 50 G= 50 B= 45 Overdrive= Strong FreeSync= On Refresh rate (Windows setting)= 144Hz

Contrast and brightness Contrast ratios An X-Rite i1Display Pro was used to measure the luminance of white and black using various monitor settings, including those explored earlier in the calibration section. From these values, static contrast ratios were calculated. The table below shows the result, with blue highlights indicating the results under our ‘Test Settings’. Black highlights indicate the highest white luminance, lowest black luminance and highest contrast ratio recorded (‘MBR’ deactivated). Assume any setting not mentioned was left at default, aside from the exceptions noted here or in the calibration section. Monitor Settings White luminance (cd/m²) Black luminance (cd/m²) Contrast ratio (x:1) 100% brightness 356 0.24 1483 80% brightness 262 0.18 1456 60% brightness 226 0.15 1507 40% brightness 181 0.12 1508 20% brightness 133 0.09 1478 0% brightness 89 0.06 1483 Gamma1 (90% brightness, Factory Defaults) 286 0.2 1430 Gamma2 287 0.2 1435 Gamma3 285 0.2 1425 Color Temp. User 289 0.2 1445 Color Temp. sRGB 278 0.2 1390 LowBlue Mode = Multimedia 284 0.2 1420 LowBlue Mode = Internet 283 0.2 1415 LowBlue Mode = Office 281 0.2 1405 LowBlue Mode = Reading 279 0.2 1395 MBR = 1 @100Hz 329 0.21 1567 MBR = 1 @120Hz 328 0.21 1562 MBR = 1 @144Hz 328 0.21 1562 MBR = 10 @100Hz 235 0.16 1469 MBR = 10 @120Hz 230 0.16 1438 MBR = 10 @144Hz 230 0.16 1438 MBR = 20 @100Hz 118 0.08 1475 MBR = 20 @120Hz 119 0.08 1488 MBR = 20 @144Hz 119 0.08 1488 Test Settings 168 0.12 1400

The average static contrast with only brightness adjusted was 1486:1, which is comfortably beyond the specified 1000:1 and as good as we’ve seen from an IPS-type panel. Whilst this isn’t as high as most VA panels would go, it provides a bit of an edge in depth for dark shades compared to most non-VA LCDs. Relatively strong contrast was maintained for all settings tested in the table, with the lowest value of 1395:1 (‘LowBlue Mode = Reading’) still comfortably exceeding specifications. Under our ‘Test Settings’ we recorded a very respectable 1400:1. The highest white luminance recorded on the table was 356 cd/m², significantly exceeding the specified 250 cd/m², whilst the minimum white luminance recorded was 89 cd/m². This gives a luminance adjustment range of 276 cd/m², although the minimum white luminance achieved (without loss of contrast) will be a bit high for some sensitive users.

The monitor also has a ‘Dynamic Contrast’ (DCR – Dynamic Contrast Ratio) setting which allows backlight brightness and gamma to adjust according to the content being displayed. As usual for such a setting, the backlight is controlled as a single unit so there’s no accounting for intricate mixtures of light and dark in a scene. The backlight responded at a reasonably relaxed pace to changes in scene brightness. It dimmed quite effectively for predominantly dark content, although tended to be quite bright for mixed content with plenty of lighter shades mixed in. As usual, we prefer manual brightness control, but this setting is there if you want to use it.





PWM (Pulse Width Modulation)

The 24G2U (24G2) uses DC (Direct Current) to dim the backlight and does not use PWM (Pulse Width Modulation) at any brightness setting. The backlight is therefore considered ‘flicker-free’, which will come as welcome news to users who are sensitive to flickering or worried about the side-effects of PWM usage. The exception to this is with ‘MBR’ active, as this is a strobe backlight function which causes the backlight to flicker at a frequency matching the refresh rate of the display.





Luminance uniformity