Today I updated my graphic card driver (8500GT) to nVidia to the latest one, 186.18 (I think). In the middle of playing Combat Arms, the screen just turned black and then the blue screen attacked me with the horrifying crash report. After that, my computer rebooted and now the screen has a bunch of horizontal squiggly line all over the screen and just to make sure I opened up dxdiag.exe to check on my 8500GT and it wasn't detected, no 3D acceleration, etc.
I am currently waiting for my 9600GSO, but this happened. I was hoping to put this card (8500GT) on one my old computer even though its crap. I left it off to let it cool down for about and hour while I went to ride bike, flip it back on, open up case to check on if fan was the problem, fan was working, but I went on and felt the card and it was extremely hot. I think it might of overheated and got corrupted or the thermal paste might of gone out or so but I'm not sure so I'll leave it to guy to help me on it.
More aboutcard problem
If the question is what happened to your 8500 GT, it sounds like it's fried. You'll know right away if the artifacts keep appearing and appear even in 2Dmode.
It does sound like it is fried. Try it in the other computer, if you get the same results it's probably dead.