Shutdown Problem

[bk6]

I just built a computer with the following specs:

i7-930
Gigabyte X58A-UDR3
Corsair 750TX
2 GB G.Skill DDR3
Intel X25M 80GB
WD 640GB SATA
Windows 7 Home Premium

It first had a Gigabyte GTX460 1GB, now it has an MSI GTX 460 1GB.


The problem that I'm having is whenver the computer utilizes the graphics card (in anything over than generic VGA mode) it will shut down either instantly or after a few moments. I've tried different drivers, flashed the MB Bios, and returned the Gigabyte card and installed an MSI card. It still happens.

I've ruled out overheating, running Prime95 and watching the temps, the i7 never goes over around 70C.

My best guesses are that the GTX 460 and Windows 7 are grossly incompatible, a mobo problem, or some kind of PSU problem.

 

[bk6]

Trying a couple of different driver sets from Nvidia, I managed to get it running for a couple of hours last night completely normally.

This morning, however, the problem is back. Since last night I was able to run it just fine, I think I can rule out a PSU problem or overheating.