If you have to ask, I doubt you are overclocking your system. Most likely your driver is crashing y6our computer. Get the latest one from
here and see if that works. Just uninstall your previous driver and replace it with this one.
If it doesn't then it might be your graphic card overheating, but let's hope this is just a software error. Most likely your old card just has some issues with newer games.
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Kamisorix has the sex appeal of a NXS
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Currently playing: Battlefield 1943 (PS3), Battlefield 2 (PC) and Wipeout pure (PSP)