I run Vista with mine & I had the same problem. Had to use one of the regular fan headers instead of the CPU fan header & disable the CPU fan header control in order to get it to work. Known bug, and no fix coming, unfortunately. Works fine running this way, though.

Quote Originally Posted by raisin View Post
Does anyone know what the current word is on the CPU fan speed issues?

I'm running a Q9550 (E0 stepping) with B18 BIOS. A cold boot into Linux and the CPU fan speed works like normal for weeks and months at a time (increasing speed with load/heat).

However, if I boot into Windows 7 (64-bit RC) the automatic fan speed will stop working at some point (not always immediately). Sometimes it gets stuck at full speed and other times at low speed. I think it depends on what the computer is doing when the BIOS gets knackered. No amount of rebooting or resetting will fix it, only a cold power-off and cut the power main will fix it. I have tried with and without installing uGuru but that seems to make no difference.

I have seen other posts about this issue but no real solutions. Some people say try changing BIOS rev or whatever but even that seems to have mixed results. Besides, I need to run B18 for my E0 CPU as far as I know.

I'm pretty positive this has something to do with Vista/Win7 because everything works normally in Linux (64-bit) and XP (32-bit). Other people complaining of this issue also seem to be running Vista or Win7. I'm not sure if the 64-bit flavor makes a difference.

If I never had to boot to Windows then I would be OK but as it is it's pretty annoying when I want to play some game that only works in Windows and it ends up screwing up my BIOS. Actually, I think it's a bug in the BIOS but obviously we're not going to get fixes from ABIT. My system runs 24/7 so cold boots put a lot of unnecessary extra stress on my system.