What the frak?
You're suppposed to flash your GPU bios, not the one on your mobo...
Try the search button, this subject was discussed many a time.
Also, while I hate to discourage you, your having made this mistake tells me you should probably not flash anything until you have done your research.
RTFM first, understand it, then flash. You're risking your hardware otherwise.
I flashed my BIOS 3 months back because my processor didn't work. I'm sorry if that's not what he meant, and I'm not going to flash my GPUs BIOS anyways.
Edit: Wording