Yesterday we have taken a closer look at AMDs latest drivers and we found some astonishing and yet concerning things. We've seen that power consumption in idle conditions is much worse than with earlier drivers. In fact, it's 55 percent higher than with with previous drivers.
In our article from on the two new drivers from AMD (Catalyst 12.10 WHQL and 12.11 Beta 4) we have mentioned that the issue is because of the graphics card not reaching the lowest power state. In other words the graphics card doesn't do the downclocking in idle correct anymore. After some further testing we also found that only the Radeon HD 7000 Series graphics cards are affected. If you have an HD 6000 or HD 5000 Series cards you wont see the issue.
At this point you can see a few screenshot which clearly show the different clock speeds:
XFX Radeon HD 7970
Radeon HD 7970 DirectCU II
Radeon HD 7870 DirectCU II
ASUS Radon HD 6950
ASUS Radon HD 6870
ASUS Radon HD 5870
AMD Catalyst 12.10 WHQL & 12.11 Beta 4 - HD 7970 Gaming Performance