before we start its a Powercolor 9800SE 256mb. Been having a problem for about a month now, what with im not quite sure but its restricting my gaming . Anywho, i'll play some games and it will suddenly gain artifacts which quickly amount up to the computer restarting for no reason other than this i suppose, sometimes it'll happen when im just sitting on the XP desktop. Sooooo i can only get this to stable out by underclocking (is that the right word?) my graphics card which will then work fine, so i thought 'hey this is a heat problem' (as i was using stock cooler) so i went out and brought a Zalman VF700-AlCu cooler, now i rigged this up and plugged the fan into the power supply, sooo it then decided it wouldnt boot up properly and when it finally did within seconds had it gathered extreme artifacts and restarted, so now im back to stock cooler and underclocked settings. Any ideas?