In the last week or so my 6850 (only had it since last xmas) has started having pretty big FPS drops in games and generally performing a lot worse than it was about 3 weeks ago. Ive reinstalled drivers, cleaned out the dust, scanned for virus's etc but it hasn't fixed it. Also if i attempt to OC my card using the ASUS programs my drivers crash and artifacts appear all over my screen before my PC freezes. Could it be not enough power from the PSU? or maybe a faulty card?