Video Locks up while playing 3d games

[Kenazo]

built a computer for a friend with the following specs:

MSI K8T Neo-FIS2R
A64-3000oem
512 megs PC3200 Samsung
200gig WD ATA100
400w PSU, not the best one, but not awful
XFX 6800

Turns out the XFX 6800 was bad, so I stuck my Radeon 9700pro in it, and he emails me with the following problem:

The computer is very good and fast, and runs the games on the highest settings--however, it locks up while I play, after a minute or two. It's done this for every 3D game. It gives me an error involving the VPU and the drivers.

Now, the 9700pro works fine in my system (AXP 2500, DFI Infinity, 512 Kingston). Any clue what might cause such an error?
Thanks.

 

[Dacalo]

Was his computer reformatted after you switched the video card? Might be the leftover drivers from 6800

 

[Kenazo]

no, I just uninstalled the nvidia drivers using the add/remove thing in Control panel.

 

[imported_JeReMY]

Try reinstalling direct x.

 

[Kenazo]

i had installed DX9c when I installed SP2, is it even a possibility to reinstall it?

 

[Kenazo]

anyone else? Still not working.

 

[Killrose]

Download and use Driver Cleaner to uninstall all Nvidia leftovers.

Make sure he has "Fastwrites" turned off in bios.

Maybe the 6800 was not bad and there is some other issue like a weak PSU, because the 9700 is not working either?

 

[Kenazo]

The 9700pro did work in my computer though, and the 6800 doesn't seem to, so I suppose it's a possibility that both of our PSU's suck, but I doubt it. I'll try Driver Cleaner though.

 

[dwcal]

It doesn't sound like it's heat or PS related, but just in case, you can try underclocking the CPU to reduce power consumption and running with the case open and maybe a house fan blowing into it. One of my old computers was a Duron 1Ghz oc'ed to 1.33Ghz with a 300W PS. After I upgraded to a Ti4200 it would freeze in 3D games after maybe 10-15 minutes. No errors, just a hard freeze with the sound looping. It was no problem if I clocked the CPU back to 1Ghz, but then what's the point of a vid card upgrade if I had to slow down the CPU? A PS upgrade fixed that eventually.