i also have the same problem with an ati radeon 9600xt, it seems that after 5-10 minutes of cs or world of warcraft there is a lock up to a bsod but without any error messages. I have fiddled with the bios settings, reisntalled all drivers, blah blah blah, could this be a reformat job, bios flash, or possibly a new rig job???? It seams to have occurred after an autoupdate of wndows xp