I have these sets of precision screwdrivers from Eklind and Wiha. I took most of the screws out from my GTX 480 pretty well. However there was this one screw near the GPU that was just stuck for some reason and got stripped. 
I had to drill out the screw head with a drill/dremel and then twist out the remaining screw with some pliers.
Nvidia should use better screws. Even good quality precision screwdrivers cannot overcome the soft Nvidia screws.

I had to drill out the screw head with a drill/dremel and then twist out the remaining screw with some pliers.
Nvidia should use better screws. Even good quality precision screwdrivers cannot overcome the soft Nvidia screws.








I get all of the other ones off, but the last one will not turn for anything, and eventually the screw is ruined. Not particularly comfortable with the idea of drilling it out either, so I've just let it be. I'll probably try to make some sort of notch in the screw head so I can unscrew it, eventually.