Seemingly random resettings

[noodlewitt]

OK, i have new(ish) system... specs are at the bottom. My problem is that whenever i try to play CS:S or HL2 I get about 30seconds to 5 minutes into the game and my computer resets, I think its a driver problem because i get fuzzy multicoloured lines for a few seconds before it resets sometimes.

But heres the killer... I have updated my video drivers, my motherboard drivers, my sound drivers, my bios with no real change...

Some other things i have tried:

-disabling Fastwrites in the catalyst control center
-using older versions of the catalyist drivers
-using omega drivers
-I thought it might be a heat problem, so i installed a beast of a fan, still it crashes
-each time i updated the vid drivers i am sure i uninstalled the previos version
-RAM tests
-Re-installation of steam, HL2, CS:S ...etc
-Adjusting Video options appears to do nothing
-Id does occasionly do the same thing when i run Doom 3, but its no where near as accute

-I dont know whether this is related or its another problem... In Italy in CS:S some of the textures are missing... I can see the wireframe in some places... only happens on that map though.

Is anyone else having problems, anyone have something to try? because i'm out of ideas ;(

*My Specs*
Powercolor Radion 9800pro
Asus A8V Deluxe Motherboard
AMD Athlon 64 3500
512RAM
200Gb Hard drive
Win XP pro SP2
430W PSU

(Sorry for the long post)

 

[graydon20]

Just a guess, but maybe it's the power supply cutting out.

 

[Tytarian]

Try setting your bios to default or optimized defaults,just to take that out of the equation,then try the games again post back for results if so inclined.

 

[FireGiver]

I had a very similar problem with my system a while ago while playing any graphics intensive game. I could play for couple of minutes then beeeeooooop!!!
I replaced the mobo... nope. I rma'd the ati radeon 9800 ... nope.
I replaced the power supply... success!!!!
I don't know why I didn't think about it eariler but I was using a cheap 350 watt ps. Looking at your specs I don't know if thats the case but I upgraded to a 500 watt and its been smooth sailing.
Other problems I've had with ati include via chipset infinite loop probs I'm not sure if thats a problem with the socket 754 or 939 though.
Hope I helped and good luck .. try another ps if it doesn't work take it back