Reeven seems to be making quite a splash. The company describes themselves:

REEVEN is a newly established international manufacturer of PC related products. REEVEN’s product lines includes the best quality of advanced CPU coolers, cooling fans, PC cases and many other items. The target of our products will be a wide range of audience under our philosophy “Professional Quality Gears”, for products that will withstand the highest demand.

So, they are offering a range of fans, heatsinks and cases to us enthusiasts. In this review we will look at Reeven’s Ouranos, which is Greek for ‘the heavens’ or ‘celestial.’ Does this heatsink provide ‘celestial’ cooling? Let us investigate.

Introduction

The Ouranos is a single tower cooler. It has a single 140 mm fan pushing air through it. The fan has a nominal speed of 1700 RPM. The heatsink comes with a low-speed adapter which reduces that to 1300 RPM. Reeven sells the fan separately as the Coldwing 14.

Reeven describes the heatsink’s features:

OURANOS is the CPU cooler with 140 mm quiet PWM fan, it is easy to upgrade to maximum efficiency with 2nd fan. Long-shape AL [aluminum] fin allows maximum heat dissipation Slim structure without conflicting with RAM zone gives wide range of compatibility 6 high-quality heatpipes guarantees superior performance

They don’t mention the fact that two of the heatpipes are 8 mm in diameter.

Specifications & Treats

Now, let’s dig a bit. First, the specifications:

Model Number RC-1401 Socket INTEL: LGA 1150 / 1151 / 1155 / 1156 / 1366 / 2011 / 2011-V3

AMD: AM2 / AM2+ / AM3 / AM3+ / FM1 / FM2 / FM2+ Overall Dimension (W)143 x (H)161 x (D)95 mm Fan Dimension 140 x 140 x 25 mm Heatpipe 4x Ø6 mm + 2x Ø8 mm Fan Speed 300~1700 (300~1300*) RPM Air Flow 16.3~92.4 (16.3~69.9*) CFM Static Pressure 0.002~0.091 (0.002~0.048*) inchH 2 O

[0.5 – 2.3 mmH 2 O, 0.5 – 1.2 mmH 2 O*]** Noise Level 5.8~36.4 (5.8~24.7*) dBA Weight (with Fan) 1030 g

*Equipped with SSA(Speed Switch Adapter) to lower the noise & RPM rate.

**Note that the static pressure conversion to mmH2O [in brackets] was added, not provided by Reeven.

Now, Reeven puts all of this on their website. The treats: the user manual and a helpful fan installation video are on the website as well. It even illustrates a problem you might have, and how to fix it, quickly, without words. Very nice, Reeven. Keep it up.

Packaging & the Ouranos

The Ouranos comes in a slick-sided retail box, covered with pictures, diagrams and print – a veritable treasure trove of information about the heatsink.

Open the box, and you find a smaller box of smaller parts. Remove that and you have the heatsink and its fan. You won’t inflict much damage on the base of the heatsink, since it’s covered with a sticky label. The fan cable has four wires, which tells you right then that it’s a PWM fan.

A side view of the Ouranos shows the 4-wire fan cable again, as well as giving us a good look at one of the fan clips. Let’s tilt it over and come closer so we can look at the heatpipes. The center two are Ø8 mm heatpipes with the rest are Ø6 mm.

A view of the fan through the fin stack shows us that the fins are not very close together and not too far apart. A close-up of the heatpipes show that they are encased by finstack material. The only way heat is going to get out of those heatpipes is through the aluminum of the fins. Is the fin stack’s grip tight enough to pass that heat through without any impediment? Our testing will find out.

The contact surface – you might call it the bottom – of the heatsink is mirror-like enough that you can see beams reflected on its surface. You can tell from the wing-nut’s reflection that the surface is not a perfect mirror, though.

Before we mount the Ouranos, let us see how much convexity it has. I have a simple rule here: The more convexity, the less time the heatsink spends on my CPU. The first picture shows just a little convexity aligned with the airflow, not too bad. The second picture shows the convexity crosswise to the airflow. Whoops! Too much. This heatsink will spend just the minimum amount of time on the CPU.

Now, this should mean nothing to you. A reviewer’s problems are not your problems. If a heatsink’s bottom is well-curved, it’s a problem for me: I have to reuse that CPU for a number of heatsinks. But for you, if you use a heatsink with a mild convexity (and the convexity here is mild), it gets you better cooling. If your CPU and the heatsink conform to each other, you get better contact. This is a good thing.

Accessories & Installation

We can see the speed reducer (an accessory), four “silicon” (silicone rubber?) washers and the backplate sitting on the manual. The rest of the first picture shows the small parts – going counter-clockwise, the LGA 775 spacer (a sticker), two fan clips, a tension screw, a tiny wrench, another tension screw, four through-shafts, the mounting bar (no slots on this for sliding screws), two nuts, two more fan clips and a small package of TIM. You must cut that open with a pair of scissors. Inside the mounting bracket we have the four LGA-2011 spacer/screws, four regular spacers and two nuts. What makes this interesting is that some manufacturers provide slots on the mounting bar to accommodate Intel and AMD. Here, the AMD through-bolts and spacers attach in different places on the mounting bracket, allowing for invariant tension screw positions. See the manual for details. Good Design.

In the next picture we see the “silicon” washers in action. The through-shafts have cams on them to prevent their turning. The rubber washers squeeze on and hold them in place. The washers also hold the backplate away from the motherboard and cushion it.

Having put together our backplate assembly, we stick it up through the motherboard. While you hold it in place, you pop on the spacers. You then screw on a nut or two. That will hold it so you can screw on the other nuts. The manual shows you how to lay down the mounting bracket … three separate times. They want you to get it right.

The Ouranos attaches itself with a torsion pressure. No springs. Take a close look at that steel. The mounting bar is grooved not to bend and the mounting bracket has thick steel. Combined with the marked convexity, this heatsink has the potential for putting a lot of pressure on the center of the CPU.

The first picture shows the gap between the RAM and the push fan. The second picture shows the RAM’s heatsinks are indeed in front of the push fan.

Testing Setup

CPU Intel i7 4790K @ 4.5 GHz Vcore Set to 1.23 V, read at up to 1.248 V Vrin Set to 1.8 V, read at down to 1.704 V GPU Intel HD Graphics 4600, integrated into the i7 4790K Motherboard Gigabyte Z97X Gaming-7 RAM Crucial Ballistix Sport Ultra Low Profile; 2 x 4 GB – 8 GB total SSD Samsung 840 EVO 500 GB + 1 TB PSU Seasonic SS-460FL 460 W Fanless Heat Stress Software Linpack with AVX2 – LinX 0.6.5 user interface Operating System Windows 10, 64-bit Core Temp Log Real Temp Ambient Temp Log Digital TEMPer USB Thermometer, with logging software Package Watt Log Intel Power Gadget 3.0 Sound Pressure Meter Tenma 72-942

Reeven provided the Ouranos. The other comparators were provided by their respective OEM’s, except for a Prolimatech Megahalems, which was purchased retail at the end of 2009, and a Prolimatech Genesis and a Noctua NH-D14 SE2011 both purchased retail at the end of 2013. Each heatsink was mounted on the night before testing. This gave the TIM most of a day to do any migrating it was going to do.

Linpack runs in surges. When the temperature is graphed, you see ragged plateaus. In looking for cooling solutions, you want to know how well a heatsink cools those plateaus. So the temps under 70 °C (the valleys) are ignored in analyzing to core temps.

Each test run was 30 minutes in duration. The last 20 minutes of each run was measured, and the core temperature logs were analyzed in Open Office spreadsheets. An Intel chip reports its temps in one degree increments, so for best accuracy these reports should be averaged in aggregate. Here the core temps were measured once a second, resulting in 1200-line spreadsheets. Three test runs were averaged.

The digital thermometer measuring air temp reported its measurements in increments of 0.1 °C. The ambient temperature was measured every five seconds, resulting in 240-line spreadsheets. The mean ambient temp was subtracted from the mean core temps, resulting in a net temp for each run. The net temps were then averaged.

The sound pressure level was measured 1 meter from the heatsink, with the motherboard set vertically, the way it would in your case. The ambient noise for this testing was 31 dBA. So the net SPL is the sound pressure level measured at 1 meter, less 31 dBA.

Results of Testing the Ouranos

The Reeven Ouranos was the best cooler tested in this rig:

The question one must ask is “Why?” This was no fluke. What you see is the average of three runs. I did one interesting thing: I held my hand downstream from the heatsink. The air was hot! Since I record the ambients for these runs, I know that the ambient was 22.4 °C, which means the air flowing out from that heatsink was more than 75.8 °C! So yes, it was doing its job. We must conclude that the convexity was just right to transfer heat, the heatpipes had a really good contact with those fins, and that the thickness of those fins and their spacing was just right. Let us not forget the two Ø8 mm heatpipes. Whatever the engineers did at Reeven, they did it right.

Conclusion

The Ouranos is one great heatsink. It is a single tower heatsink and still, it does a great job cooling. It seems that single tower heatsinks are making a comeback. First, the Noctua NH-U14S has been doing as well as the tandem tower heatsinks in some reviews. Then, the Noctua C14S with heatpipes oriented vertically did amazingly well. Next, the Scythe Ninja 4 beat the tandem tower rigs in my review. Now the Reeven Ouranos beat even that. I am putting the D15 and the D15S on my rig between test runs for other heatsinks, and they are cooling as well as they always have. I am testing my overclock to make sure the system is making just as much heat as it did for the other heatsinks. No doubt about it: the Reeven Ouranos is one devil of a heatsink. It pours out the heat.

The heatsink bottom, the contact surface, is a little convex. This is more of a problem for me than it is for you. The mounting bar is loose, but without slots for the tensioning screws, the mount is OK. It could be easier, but it is OK.

Mounting the Ouranos is straightforward. Overall, the Ouranos is a fine heatsink.

MSRP: $49.95

Ouranos Pros

Online Manual

Online Fan Installation Guide

Fan Clips and Unclips easily

Cools like the devil

Ouranos Cons

Sleeve Bearing Fan

Click the stamp for an explanation of what this means.

Ed Hume (ehume)