BF2S Forums Video Card problem

I've got a 7800GT.

Here are the symptoms. I started up my pc this morning, and after it gets to desktop, I've got about 10 seconds before the screen filled with artifacts, much like if you were to go to a channel that didn't exist on TV (black and white alternating throughout).

Yesterday, I downloaded and installed nvidia's ntune, so that I could monitor the temperature. It was idling at 50C, which was fine. However, when I started my computer up today, my screen did what I mentioned above. I'd be more likely to believe that it is a hardware problem vs. a new software issue. The thing is, it hangs once the screen gets full, and I can't do anything after that (would love to try uninstalling ntune to see if that's it).

Does this sound right to you? Have any of you had issues with ntune, or heard of anything wacky like this happening because of it?

I'm going to give it a good cleaning later and see if that improves things, because it almost seems like it's overheating. I guess my fan could have failed when I turned it on, or the video card just died regardless.