I've been using the stock fan for the i7 in my build, but today I upgraded to the Xigmatec Dark Knight cooler. I'm not sure if this has anything to do with the GPU's, but I want to provide as much info as possible.
Before I upgraded, my gpu's were working perfectly. I could run Crysis no problem.
After I installed the fan, I pressed the power button on my case, and it didn't turn on. I tried to press the motherboard green button thing on the EVGA x58 mobo, but I might have pushed the clear cmos or something button. When I ran crysis the r_displayinfo showed the logos and menu going at 100fps+ but it looked like it was going at less than 10. I noticed that the gpu memory counter says 335MB instead of 1725MB, which I'm guessing means that there is a problem.
The device manager says I'm at driver version 188.8.131.5238 released on 7/14/2009.
I know the cards aren't dead because I'm using dual monitors and they're working fine albeit slower than before.
Sorry if any of this sounds strangely worded, typed it in a hurry.