Well, not really my entire computer, just not my graphics card. When I play crysis 2, my hardware monitor shows that the core clock only runs at a maximum of 399mhz. I would be fine with this if I had my old 8600gts's, but I have a 285gtx that is overclocked to 735mhz. This is severely destroying my framerate by the way.

Hmmm. It seams Nvida made some shit with the latest drivers? I have GF 9600 and all is working fine at ''not max, but close to max details.''. I don't have latest drivers.
Only thing I noticed: my card temperature rises to 70 C after 1-1.30 h of playing.;}

Ok, new drivers fixed it. So simple

However, now I cant find my boxfan. It's going to constantly overheat(i've let it go up to 80 C so far, the computer crashes at 90 C), I really need to get watercooling sometime. But I'm happy with the perfect framerate now. It's also letting me take the settings up to extreme; before it would only let it go to Very High.

hm...I think the HD Series from ATI are still better then Nvidia....

I'd really say that they're equal now, price to performance.
For me it's just that I decided to get one with a crappy heatsink/ fan.

you can get custom heatsinks for your videocard