6800gs problem?

[DaRkLoRd666]

i have
msi rx480m2
1gb patriot
+3000 amd 64
6800gs (old one was x300)
everything else is integrated
before the upgrade everything worked fine but afterward runing a graphic intensive game like counterstirke source (for 3 min) or warcraft3 (for 10 min) the game freezes and sound crakles for about sec and sometimes resumes or the game crashes but does not restart, then no other directx will work untill a restart or in counterstrike freezes for about 30 sec then the computer restarts.
i have tryed all i can think of (drivers, bios, 3rd party drivers) my intigrated x200 works fine.
do i have to get the card replaced or is there some kind of hardware problem.

 

[StarLancer]

Disable your onboard graphics in Bios
Run Driver Cleaner and remove all Nvidia/ATi video card drivers
re-install your nvidia drivers

see if that helps.

 

[DaRkLoRd666]

that dident work, could the problem be that i have a 20 pin psu pluging into a 24pin motherboard and since the 6800gs reqires more power then the x300 that could cause a short or somthin?

 

[drum]

what psu is it exactly?

 

[DaRkLoRd666]

its the lc-a420atx (i think im not at that comp right now) by turbolink (a company that i cant find or ever heard of before)

 

[DaRkLoRd666]

never mind.... the powersupply is not the problem, i replaced it with a 24pin connecter 600w one that has good reviews... i will now try geting an rma # and hopefully the replacement one will work well. does anyone know of any compatibility issues with the evga 6800gs and my msi rx480m2 (ati x200 intigrated graphics) plz help me out