Cooling Efficiency and Acoustic Performance
Cooling Efficiency Tests
The results of our comparative cooler testing are given on the diagram and in the table below:
At first let’s discuss the results demonstrated by our testing participants with their default fans. As we have expected, the least efficient cooler is the reference boxed cooler that comes with the Intel Core i7-980X with the fan working in the moderate speed mode (800-1800 RPM). However, we have to give this cooler due credit for coping with pretty seriously overclocked six-core processor at increased core voltage. If you switch the fan into Performance mode reaching the maximum speed of 2640 RPM, the peak CPU temperature will drop by another 6°C, which is quite good.
One step closer to the top is Scythe Yasya cooler. In the moderate acoustic mode of its default fan working in 500-1400 RPM speed interval, Yasya cools 1°C better than the reference cooler of our six-core CPU at its maximum speed. If we expand the fan rotation speed range to the maximum (720-1960 RPM), Scythe Yasya gains very little: the peak CPU temperature drops by only 3°C. As a result the new cooler from the Japanese maker takes only the fifth place out of six at this point.
Spire TherMax Eclipse II looks quite fine as it outperforms Scythe Yasya by 1°C in quiet mode with two fans at 1100 RPM and by 6°C at maximum fan speed. Of course, in this case the noise from the Spire cooler is higher than that from Scythe. Zalman CNPS10X Performa does even better: with one default fan it manages to successfully compete against TherMax Eclipse II with two fans onboard, even though the fan of the Zalman cooler rotates with lower maximum speed. Noctua NH-D14 with its default fans is again ahead of everyone else, besides the roaring Zalman and Spire coolers. And as for Baram-2010, it comes without a fan by default, so I guess it is time to move on to comparing the coolers’ performance when tested with two identical Thermalright fans.
Unfortunately, this part of our test session produced less interesting results than we have expected, because they turned out all very close. We can notice some differences in quiet fan mode at 1100 RPM. There are two “outsiders” here: Scythe Yasya and Spire TherMax Eclipse II, a “medium runner” – Noctua NH-D14 and two “leaders” – Zalman CNPS10X Performa and ThermoLab Baram-2010. I put all three words in quotation marks for a reason: the difference between these three coolers is less than 3°C, and at maximum rotation speed of our Thermalright fans all five coolers are almost equally efficient. So, what shall we do? The answer is fairly simple: we have to test our processor with each participating cooler to check out how far we will be able to overclock it, especially since its potential is far from being exhausted.
Well, Scythe Yasya proved capable of pushing the clock frequency of our six-core CPU to 4488 MHz at 1.475 V core voltage. With two fans working at 1100 RPM (quiet mode), the temperature of the hottest CPU core hit the dangerous level of 92°C, and at 2040 RPM it dropped down to 82°C:
As we see, despite some statements made by several other reviewers, Scythe coolers are not just fit for quad-core CPUs, but can ensure stable system operation even with seriously overclocked six-core processors.
Spire TherMax Eclipse II cooler with heatpipe direct touch technology didn’t blow us away by its performance with an overclocked six-core processor. With two fans working at 1100 RPM (quiet mode), Intel Core i7-980X remained stable at 4440 MHz frequency and 1.45 V voltage, while its peak temperatures stayed at 86°C. At maximum fan speed the frequency increased only to 4488 MHz at 1.475 V Vcore and 84°C CPU temperature:
Zalman CNPS10X Performa proved more efficient than Spire and Scythe products. With two fans working at 1100 RPM (quiet mode), we managed to overclock our processor to 4461 MHz at 1.475 V Vcore and maximum temperature of the hottest core around 88°C. At maximum fan rotation speed the CPU frequency hit the today’s record level of 4512 MHz at 1.475 V core voltage and 82°C temperature:
No matter how surprising it may seem, Noctua NH-D14 didn’t perform best of all today having taken the proud second place. With two fans working at 1100 RPM (quiet mode), Noctua NH-D14 and ThermoLab Baram-2010 demonstrated absolutely identical results during maximum CPU overclocking test: 4488 MHz frequency at 1.475 V Vcore and 87°C processor temperature. However, at the maximum fan speed of 2040 RPM Baram-2010 managed to outperform its neck-and-neck rival by 2°C:
What a surprise! I am sure no one expected anything like that to happen. The modest and relatively lightweight Baram-2010 outperformed the monstrous NH-D14! At the same time, it is important to understand that these results are obtained on a CPU with an uneven heat-spreader, so the efficiency of cooling using any of the tested products depends significantly on the quality of contact between the cooler base and the processor heat-spreader. Of course, ideally flat base of Baram-2010 has a larger contact spot on the Intel Core i7-980X heat-spreader than the slightly protuberant base of the Noctua NH-D14 cooler (which you can clearly see from the imprint photos above). This fact certainly has its say in the end result of the test.
Therefore, in one of our upcoming articles we are going to discuss the results obtained on a CPU with a perfectly lapped heat-spreader and how they compare against the results obtained today. Hopefully, a CPU with a lapped heat-spreader will overclock even better. And in the meanwhile let’s talk a bit about the acoustic performance of the today’s testing participants.
Due to smaller distance between the noise-meter and the fan rotor of 150 mm, we can now measure the noise from the coolers when tested not only with one, but also with two fans (the second fan being installed on the back of the heatsink). The graph below shows the obtained results:
If we put low-speed Noctua cooling fans aside, we can conclude that Spire cooler has the next quietest fans onboard. It is a real pity that there are no devices for adjusting their rotation speed and that they do not support PWM controlling. Far not every user out there is ready to put up with two fans spinning at more than 2300 RPM in their home system. Zalman and Scythe fans generate about the same noise, but Zalman seems to sound more pleasant. The loudest cooler of all tested today would be the boxed Intel cooler that comes with the Core i7-980X Extreme Edition processor. At high rotation speed its fan starts clinking, so that only the “Q” mode (800-1800 RPM) is in fact acceptable. And as for the noise from the 140 mm Noctua fans, we have already discussed it before: they remain pretty quiet up to 820-840 RPM and start producing too much noise at higher speeds.