Irritating Display Problem

(I Originally posted this in the General Homebuilt section, but I figured I'd get more responses here since it's most likely a problem with the graphics card)

Kind of a strange problem if you ask me. Completely out of the blue, my display just turns a solid colour. Sometimes it's after 10 minutes and sometimes it's after an hour. It does this when I'm watching movies, listening to music or when the computer is idle. It also does it when there is a load on the processor. The only time this doesn't happen is when I'm playing graphics intensive games. I've had this problem since I first built the computer about a month ago. I have to shut down or reset via the case's front panel whenever this happens, as the display won't return to normal.

I have not overclocked my system at all yet, and a clean install of Windows hasn't cured the problem. BIOS is at the latest revision and all drivers are up to date as far as I'm aware. All my temps are within normal limits also.


Any help stopping this problem would be appreciated.

Components are as follows:

ASUS P5W-DH
Core 2 Duo E6600 with Scythe Ninja Plus installed
Sapphire X1900XT 256MB with Accelero X2 installed
2GB Corsair XMS2-6400C4
OCZ GameXStream 600w
2x Seagate 7200.10 320GB (non-raid)
Antec P180