I got a Galaxy 8800GT about a month ago and somehow it seems to be unstable with stock speed because when I play C&C3 it usually crashes (the program closes with no error message) after about half an hour. I am quite certain that the video card is to blame since I have never been able to go past 15 minutes without an error in the ATItool stress test. I use an aftermarket cooler (vf900) but the ramsinks arent installed because I can't get them off my old card. Once, I forgot to plug in the cooler fan and I got a bsod but my card did not reach a temperature higher than 65C according to speedfan (I was not gaming), so I doubt that it was permanently damaged. The card usually idles around 50C and gets to 55C while gaming, and to 68C while stress testing. I tried playing portal and UT3 for more than an hour each, and no problem, but I think C&C3 pushes the card harder. Any ideas on the cause and potential solutions?

No, mine was a standard 1800MHz speed. Indeed, some "factory overclocked"versions are clocked too high and need to be clocked down, but I just have the regular model. I have been playing C&C for a few hours and there was no crash, I guess this is periodic. I'l be running ATItool for the next few minutes to see how it goes.

No, I took the most recent driver, that worked with my old card. I guess it might be a driver problem indeed, I'l give it a try.