Games keep crashing my PC!!

Greetings fellow geeks,

First of all here is my system:

- 600W Colorit Silent PSU (with 30A on the 12V rail)
- AMD64 Dual Core 5600 CPU
- 2GB 6400 800mhz OCZ RAM (ATi Certified with nice red heatsinks)
- 8600GTS XXX OC Graphics Card
- 250GB C: and 500GB Spare drive (both SATA)
- everything is stock and I haven't overclocked (the g/card was factory overclocked)

OK so my problem is that I don't play games so much (well that's not THE problem but could been seen as one to some people) but when I do I play games like Unreal Tournament 3 and Call of Duty 4, Crysis etc. everything worked fine a week ago on XP Pro then I upgraded to Vista...all good except for the games. I'd play for about 10 minutes then the screen would freeze, nothing would work and the sound would loop. No matter how long I left it the situation wouldn't change most of the time. Once I got BSOD (can't remember code), another time I got (while playing CoD4) an error code saying iw3sp.exe was corrupt, but most of the time it just freezes...oh actually earlier on today the screen went black but the game continued! I changed back to XP Pro yesterday and still have the same problems.

What i've done so far to try and sort it (none of which has worked!) is play in safe mode, play on the lowest possible settings (even though the highest seemed to be OK before...but not in Crysis which is to be expected), monitor my temps and speeds using Riva Tuner (but I heard that itself can cause game freezing so I got rid of it) and monitored temps and speeds and % usage of RAM CPU and graphics using Nvidia ntune and nothing seems out of the ordinary.

So i've tried 2 different operating systems and it's happening to multiple games which makes me think it's a hardware problem, but there seems to be no problem on paper. Everything is near new and the PSU has 30A on the 12V rail which should be more than enough!

ANY thoughts will be greatly appreciated......thanks in advance geekers...

p.s. all my drivers are up to date (even updated my PLUG AND PLAY monitor because of the little episode where the screen went black but gameplay continued!!!) and directx is up to date as well.

p.p.s. Oh and another thing...when I tried turning my computer on this morning it wouldn't. The damn light on the mother board just constantly flashed at me on-off-on-off-on-off and so maybe it COULD be a problem with my PSU...

 

I assume you have done all the obvious, patching the games, fully updating your OS ,et cetera? Speaking of that, did you actually upgrade from XP to Vista, or did you do a clean install?

 

Are you watching your temps. CPU or MOBO could be getting hot under the load of a game.