Problem with 8800 GTX, need help please...

Right, i'm having a problem with what seems like the textures in some games. These problems are quite intermittent and only seem to happen when the app has been running for an hour or more. I managed to get some pics of what seems to me like texture errors: -


Original (what it should look like)








What happens is that the game will appear to hang and then every 10 seconds or so it will update the image on the screen with different problem. Most of the time it seems like the textures have gotten mixed up and sometimes the lighting goes a wrong.

Sometimes you can get to the desktop and close the app, when you can do this all works fine, unless you go into another 3D app ant it will hang like before. The last image in this post is what happened when i launched mass effect again. Once I restart the PC everything works fine, until it happens again.

It isn't only Mass Effect, I have seen similar things happen to Unreal Tournament 3, GTA San Andreas, Morrowind, Crysis, Quake 4, Gears of War and a few others.

My PC is relatively new, maybe about 6 months old, and all the parts were bought brand new. here is my PC spec: -

Windows XP Pro
Motherboard - Gigabyte GA-MA770-DS3
MEM - 2GB OCZ Platinum DDR2 800 stock
HDD - Samsung SpinPoint 500 GB
CPU - AMD X2 5000+ (Black ED) stock (with Zalman cooler)
GPU - Nvidia 8800GTX 768MB (G80) stock (175.19)
Sound - Audigy 2
PSU - OCZ Silent Stealth 600W

I have been racking my brains on this issue and have checked several things already: -

done memtest for 6 hours - passed
ran prime 95 over night - passed
checked temps - CPU MAX 48 - GPU 85 MAX'ish
removed components and re-seated them several times
Ran with all fans up full (noisy as hell) - still hangs
changed the memory voltage to 2.10V (what it should be)
disabled bios shadowing
removed drivers (fully) and re-install - still hangs

I have also run folding@home for 24 hours strait (the new GPU version) with no problems. I never run it when gaming though.

I am at a loss! I have a couple of ideas of what it could be but could really do with some second opinions about this. This is what I think the problem is: -

1. The PSU is not man enough to run the 8800GTX (although 600W is the recommended)
2. Bad GPU, not so sure about this because I have had games running 6 hours + with no problems. if it was bad then it should happen shortly after starting the app


If anyone can help I would appreateate it, alot!
If you need any more info please let me know and I will provide it.

I feel your pain there, I checked your specs, they are all definatly good enough for the games you are playing and psu is way above minimum!! 8800gtx requires at least 450watt so the problem wasn't in your power unless the psu is defective, It is very interesting what could of happened, maybe if you replaced it for another one it could of worked idk, but very strange indeed!