Apple posted and quickly pulled an NVIDIA flasher utilty last week. I’ve read the reason it was pulled was because the original flasher posted by Apple enabled NVIDIA PC cards to work in Apple computers. On Macintouch, John Neil – Director of Mac Software at Nvidia clears this up (my emphasis):
[…] NVIDIA sells chips, not cards. It doesn’t matter to what video card is used as long as it has one of our GPUs on it. The requirement that PC boards not work with Mac FCode comes from Apple.
I’ve got a plaintalk mike for sale if anyone wants one.