Cooling Efficiency and Acoustic Performance
Cooling Efficiency Tests
The coolers on the diagrams below are listed in practically the same order as we have been discussing them today. The results are the following:
First of all I have to point out minimal difference in CPU temperature with the aluminum ZEROtherm BTF80 and copper BTF90 models. Looks like the heatsink design turned out so efficient that replacing the aluminum plates with copper didn’t really improve that much, so I believe it doesn’t make much sense to pay extra for a heavier cooler.
The next one in the ranks is the overclocker model called ZEROtherm BTF92 O.E. Don’t be surprised that it lost to the previous two models here in quiet fan mode, because the other two models have fans supporting PWM and hence have about ~1,000RPM advantage. However, once the fan of the BTF92 O.E. speeds up, the cooler easily outperforms the two younger brothers getting about 3-4ºC ahead of them in peak temperature.
However, we were really impressed with the performance of the top model - ZEROtherm Nirvana NV120 Premium. It is quite logical that this cooler demonstrated better efficiency than the previous three solutions from APACK and we had actually expected it to. However, we were very pleasantly surprised to see that Nirvana NV120 Premium was at least as efficient as Thermalright Ultra-120 eXtreme super-cooler with high-quality Scythe fan. So, we can state with all certainty that overclocking fans just got another super-cooler to consider.
You don’t see the results of ZEROtherm BTF95 Fanless on the diagram, do you? True, because the passive solutions cannot cope with cooling a quad-core processor overclocked to 4GHz frequency. This is not surprising at all, as BTF95 Fanless was not designed for that. However, it will do perfectly fine with cooling an Intel Core 2 Extreme QX9650 processor working at its nominal speed. It will maintain its temperature at steady 68ºC under maximum workload in a well-ventilated closed system case:
Click to enlarge
In fact, you can even overclock this quad-core processor a little bit with ZEROtherm BTF95 Fanless cooler: to 3.41GHz by raising the Vcore to 1.325V. In this case the hottest core under maximum workload will heat up to 88ºC (and looks like there is still way to go further):
Click to enlarge
All in all, this is a very good result for a cooling solution like that, I should say.