Excellent cooling performance for 70 euros? Reeven Okeanos

Test procedures

Reeven seems like a smaller manufacturer, but it does not matter at all in the case of Okeanos. This cooler can definitely stand its ground. It could be used as a good example in many ways. There are some drawbacks for sure, but you get really decent cooling performance for the money.

Basic parameters

*These measures indicate distances between the cooler and RAM slots, or more precisely the nearest PCIe × 16 slot.
**The data reflect the situation on Mini-ITX boards which typically have 50 mm from the center of the socket to the first slot. With the ATX format, it can be up to 7 mm more and that means one extra slot and a wider compatibility than is mentioned in the table. We measured the height limit with fans that are aligned with the maximum specified coolers height.
***It is not a part of the accessories, you need to send a requested to the manufacturer. The assembly kit for AM4 is free, you only pay for the shipping.

Details

The design of the heatsink looks really fine, and the manufacturer made several good decisions. Dual tower is ground zero for every air cooler with big ambitions. However, Reeven has some nice features that distinguish it from others. First of all, it has a narrower profile (135 mm), which makes Okeanos one of the narrowest dual tower CPU coolers. What is interesting is that the gap between the towers provides a lot of space (6.5 mm) for more comfortable mounting of a fan.

Remarkable is the configuration of heatpipes. There are two 8 mm thick pipes above the center of the IHS, where the heat exchange is most intense. The remaining four pipes are 6 mm thick, which is basically a standard. Interesting are also routes of these pipes across and through the radiator, they look like triangles. The thinner pipes are adjusted to the direction of the airflow behind each other and closer to the sides. The thicker pipes are oriented more towards the center of the heatsink. All this makes it easier to use the whole area effectively, and Okeanos heatsink should be excellent in its weight category (782 g).

However, the fans are average, or perhaps below average. They have cheap bearings which produce rustling and that does not fit into quiet configurations very much. The second major problem is related to the fact that each fan has its own different size (120 + 140 mm). There is nothing wrong with two fans with different measures, but the inconsistency in their flow definitely is an issue. Even without an anemometer, it is obvious that the front fan has a higher flow rate than the middle one. The increase in the flow rate is not consistent even according to the same voltage, which can be seen in the chart. The noise level at 1100 – 1200 rpm (measured with the front fan, rear is 10 – 20 % slower) rises a bit and then remains linear. And the question is not whether the inconsistency of the airflow has negative effect on the cooling performance, but rather how significant this negative effect is.

And then there is another curiosity around the fans. Compared to Noctua NF-A15, their consumption is at least twice as big with similar flow rate. While NF-A15 has only 1.4 watts at 12V, Reeven Cold Wings consume 3 W with similar airflow, and 9 W with maximum airflow. The start-up voltage is also quite big – 7.6 V.

The configuration of a smaller and a bigger fan is not very common these days (usually it’s 140 mm + 140 mm), but we think it’s a shame. Loss of efficiency per unit of noise is nothing terrible with 120-mm fans, but a smaller frame extends compatibility with RAM – 3cm (90% of modules are higher) and 5 cm (90% of modules are smaller) is quite a difference.

Compatibility with the PCIe slot is also very good, despite the symmetrical design. Also, there is no collision on the boards with the first GPU slot near the socket. Complicated dismantling is, of course, a different story. But that should be resolved by manufacturers of boards.

We appreciate the possibility to install the cooler in two ways on AMD sockets. Thanks to a handy frame, the fans can be directed to both the rear and the upper outtake. And although this may seem like a matter of course, it is quite rare in fact. Most coolers cannot be installed in two positions on AMD AM3/4.

Reeven seems like a smaller manufacturer, but it does not matter at all in the case of Okeanos. This cooler can definitely stand its ground. It could be used as a good example in many ways. There are some drawbacks for sure, but you get really decent cooling performance for the money.

Test procedures

Tests begin with the analysis of fans. Using the Gophert CPS-3205 II laboratory power supply and the UNI-T UT372 laser tachometer, we detected the initial speed. That means determining the minimum voltage required to move the rotor in the idle stage. Subsequently, we regulated the revolutions by hundreds (from 400 rpm to the round maximum), which gave us the first part of the data to create a curve that indicates the noise increase according to rpm. To make the results as accurate as possible we took the average values of 30 seconds long sequences and regulated the fans by the hundredths of volt until the tachometer reached a specific value, for example 800 rpm. Finally, we noted down the maximum rpm and put values into the parameters table.

To assign a specific noise level to a specific speed, we put the coolers with corresponding voltages to the soundproof box in which we measured the noise. This was done using the Reed R8080 sound level meter that was recalibrated before each set of measurements. The positions of the polyethylene pad on which the coolers were fixed, and the sound level meter were always the same. To achieve the most precise logging even with the lowest flow the distance between the sensor of the meter and the fan was approximately 25 cm. Each measurement was performed in real time. The meter sent 30 sound samples to the computer, from which we took the average value and put it into the charts. The most important part was to find and to align the fan settings to fixed noise levels. In this case, 45, 42, 39, 36, 33, and 31 dBA were selected, and with the exception of the last and the penultimate mode, each further decrease of rpm reduced the noise level by a half. On the one side there was noisy 45 dBA and on the other almost completely silent 31 dBA.

If one of the modes is missing in the charts, it is either due to insufficient cooling performance or because it was not possible to regulate the fan to the desired noise level. Each test lasted 600 seconds. We simulated the burn in IntelBurnTest (7500 MB) and the result represents the average of maximum temperatures of CPU cores, which were captured in Core Temp. At the time when some of the cores reached 95 °C, the tests were interrupted and considered unsuccessful.

Cooling performance tests were done in our plexiglass wind tunnel with a motherboard in the vertical position, just like in a usual tower case. The scheme of the system cooling was traditional, balanced flow was provided by four Noctua NF-A12S PWM fans. Two were at the input and two at the output, regulated to 550 rpm.

The intake air temperature was 21 – 21.3 °C, ensured in our air-conditioned lab so we could also accurately measure the automatic regulation PWM. Only during this process we put the processor with TDP 140 W back to the factory settings. The curve of the profile of the impulse modulation was set, regarding to low noise level, to 20 % ≤ 20 °C – 30 % ≤ 40 °C – 40 % ≤ 60 °C – 100 % ≤ 90 °C.

*Without overclocking, the power consumption of the configuration during IntelBurnTest load was around 170 W; 225 W with overclocking (approximately 180 watts by processor).

Reeven seems like a smaller manufacturer, but it does not matter at all in the case of Okeanos. This cooler can definitely stand its ground. It could be used as a good example in many ways. There are some drawbacks for sure, but you get really decent cooling performance for the money.

Automatic regulation

Reeven seems like a smaller manufacturer, but it does not matter at all in the case of Okeanos. This cooler can definitely stand its ground. It could be used as a good example in many ways. There are some drawbacks for sure, but you get really decent cooling performance for the money.

Max. RPM

Reeven seems like a smaller manufacturer, but it does not matter at all in the case of Okeanos. This cooler can definitely stand its ground. It could be used as a good example in many ways. There are some drawbacks for sure, but you get really decent cooling performance for the money.

45 and 42 dBA

Reeven seems like a smaller manufacturer, but it does not matter at all in the case of Okeanos. This cooler can definitely stand its ground. It could be used as a good example in many ways. There are some drawbacks for sure, but you get really decent cooling performance for the money.

39 and 36 dBA

Reeven seems like a smaller manufacturer, but it does not matter at all in the case of Okeanos. This cooler can definitely stand its ground. It could be used as a good example in many ways. There are some drawbacks for sure, but you get really decent cooling performance for the money.

33 and 31 dBA

Reeven seems like a smaller manufacturer, but it does not matter at all in the case of Okeanos. This cooler can definitely stand its ground. It could be used as a good example in many ways. There are some drawbacks for sure, but you get really decent cooling performance for the money.

Conclusion

Coolers like Reeven Okeanos are quite rare. There are not many high-end heatsinks with common fans for a reasonable price. Even if you find a cooler that fits this descriptions, it is difficult to acquire one because shops are usually out of stock.  Its closest opponent, Raijintek Tisi, has a similar problem.

Okeanos undoubtedly has excellent heatsink, but we cannot say the same about the fans. Cold Wings are not exactly bad, but they have all the features of low-end fans, in addition to poor optimization for working together. The smaller one (120 mm) has a higher flow rate with the same voltage, which is not very good for performance. But we are looking forward to extra tests with industrial Noctua fans. However, if you do not mind the “wheezing“ of the bearings, you will survive without replacing them. Consumption is even higher than you would expect and the fans will not start even at 7 V, but impulse regulation works nicely.

Regardless of all the imperfections of the supplied fans, the heatsink is a worthy challenger even for NH-D15, and surprisingly (since it is a smaller heatsink) it does not fall behind even in really quiet modes – at 33 dBA, Okeanos is worse only by 1°C, and it is the same scenario with max. power. However, running the cooler at 12 V with enormous noise is irrational. The difference in performance between the maximum ~ 1795 rpm (57.3 dBA) and ~ 1220 rpm (45 dBA) is almost negligible.

Compatibility with memory modules and graphics cards is extraordinary. It is slightly more complicated with AMD AM4 support. The assembly kit for Ryzen is not part of the supplied equipment and you need to send a request to the manufacturer. Reeven will send it to you for free (you pay only for the shipping).

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• Contents
• Parameters and details
• Test procedures
• Automatic regulation
• Max. RPM
• 45 and 42 dBA
• 39 and 36 dBA
• 33 and 31 dBA
• Conclusion