This is about an original Mac Pro. So I hope I post in the right Forum, but the very nature of my question has more to do with hacking as with anything else

So I wonder if it is possible to use a flashed 1024MB Version of the Geforce 8800GT in a Mac Pro - both Vista and OS X should work without any problems, but I wouldn't mind if the additional 512MB VRAM would only be recognized under Vista.

I am searching for an answer for days now, and in the meantime I think it might not work (at least there was one example where it didn't work) - but I can be very bullheaded in regard to computer problems, so I haven't given up hope completely

If anyone has tried that with or without success, I would appreciate any input.