Let’s see, which of the two will be more efficient: Asus DirectCU II or Spire SkyMax:
Asus DirectCU II is an indisputable winner here, but we can’t say that Spire SkyMax was defeated in this test, either. Overall, Spire proved to be a very efficient cooler/ if we compare the SkyMax cooler with its fans at 1400 RPM against Asus cooler at 1500 RPM, the Spire product will be only 5°C behind in peak GPU temperature, which is really insignificant for GeForce GTX 680 overclocked to 1215 MHz with the resulting temperature at only 67°C. At the minimal speed of 1000 RPM Spire cooler also coped with the GPU of our High-End graphics card keeping the temperature below 70°C at all times. If we compare Asus DirectCU II and Spire SkyMax at the maximum rotation speeds of their fans, the former will be 11°C more efficient, which is, actually, not surprising at all considering the type of fans and their maximum rotation speed range.
In terms of VRM components temperature, which can also be monitored on Asus GeForce GTX 680 DirectCU II TOP graphics card, the efficiency difference between the testing participants becomes more prominent. Asus DirectCU II is still the leader here keeping the VRM temperature at 61°C at 3390 RPM fan speed. Spire SkyMax with the fans rotating at 2830 RPM is 5°C behind. Further lowering of the fan rotation speed indicates that the temperature increases rapidly in the interval between 2830 and 2200 RPM and between 1800 and 1400 RPM. In the worst case, at the minimal rotation speed of 1000 RPM, the graphics card voltage regulator components heated up to 84°C, which is still quite acceptable for High-End graphics cards.
Obviously, Spire SkyMax is a highly efficient cooler. But how noisy is it?
As we have already mentioned earlier today, we were unable to compare the cooling efficiency of the new Spire SkyMax and the recently tested Arctic Accelero Xtreme 7970 because of constructive compatibility issues. Nevertheless, we can still compare their acoustic performance. The results of Arctic, Asus and Spire noise tests are summed up on the following graph:
Spire SkyMax is indeed noisier than the other two coolers, but the difference is minimal (especially between it and the Arctic cooler). The new cooler from Spire remains acoustically comfortable up to 1200 RPM, and at 950-1000 RPM it is exceptionally quiet. The fans do not crackle, vibrate or cling, which may often happen. Overall, these are very high-quality fans. And the winner of our acoustics test is Asus DirectCU II, which once again confirmed its status of the best proprietary VGA cooler.
Recalling our previous review of a VGA cooler we could conclude that Spire SkyMax is a very capable cooler. When all three of its fans rotate at 1000 RPM inside a closed system case, this cooler can cope with the today’s fastest single-GPU GeForce GTX 680 graphics accelerator working at 1215 MHz speed and with 1.175 V voltage, while maintaining GPU temperature at 69°C and the VRM temperature – at 84°C. And the noise level in this case will remain exceptionally low. This is a truly admirable result! No doubt, Spire SkyMax will satisfy even the most demanding users out there in both: cooling efficiency as well as noise. On top of that it comes at a significantly lower price than Arctic products, for example. The only thing we wish Spire would do is expand the list of supported graphics accelerators or provide additional retention kits for their highly successful product.
Summing up everything we have just said, we are proud to award the new Spire SkyMax with our Recommended Buy title: