I only got my 8800GT on Friday, but today, there have been three occasions on which I had my screen suddenly artifact, then my system locks up. I updated to the 196.something driver, so it's possible that it has something to do with it. My power supply is only 550W, so I was thinking this might be a symptom of not having enough power. It's pretty disconcerting, seeing as the card is so new, so I was wondering if anyone could shed some light on this.