9800pro borked!?

Hi, recently my 9800 pro overclocked and working at 410/355 started getting glitches and graphical errors in counter-strike. Then it started in pirates, and now it wont run 3dmark2001 looping without crashing. It was doing this before i re-formatted and re-installed the 4.12 drivers and it's still doing it. Is there any other tests or things I can do to test whether it's gone or not. By the way It's fitted with an ati silencer 1 and I have re-fitted that to test whether that was the problem but it's still happening. ANy help would be greatly appreciated, thanks,John.

I take it you have tried it at stcok speeds and it still does the same thing?

m@

yes, unfortunately. I have everything at stock and it's still doing it. I'm gonna put the old heatsink on and request and RMA from....EBUYER.

do you think e-buyer will notice that i have tampered with it?, i reset it to stock speeds and everything.