wired glitch, possibly performance based

[Bobson00]

Playing the Witcher EE my game keeps momentarly freezing, the screen goes black and almost tabs out of the game and then goes back to the game. This happens on and off usually every 5 or so minutes. Any idea why?

I've got a GeForce GTS 250, 4096mb ram and a AMD phenom II x4 925 Processer (4 cpus), -2.8ghz

Other games like dark souls run fine.