Dell :: Bad Gpu Or Bad Driver

I was playing thief deadly shadows on my e1705 when the screen freaked out and showed this message.(look at pic)

I held the power button to shut it off and when i rebooted the lcd would not show a picture. I figure the gpu is dead. Well i left it alone for the weekend and booted it up Monday morning to see what it does and it was working ok. It took a bit longer than usual to get past the DELL boot screen but it showed no glitches or anything. so I played thief for about 30 minutes and the screen freaked out again and displayed the message. my question is this a driver problem or a hardware problem? I started using a new tweakforce driver to overclock the go 7800 about a month ago. I used a different tweakforce driver for years to overclock before and never had a problem. I used to use an 80.xx driver and I switched to a 94.xx a month before the crash.