Sapphire HD 7950 Mac Edition Graphics Card -
| posts: 26,911 | Location: Guru3D testlab
Sapphire has introduced another graphics card to its range, the HD 7950 Mac Edition. Designed specifically for Apple Mac Pro series of desktop computers, the card sports 1792 Stream Processors, a core...
The bios aren't for the efi that apple uses for their macs, it'll work under a windows environment in a Mac Pro, but that's it. You can flash some cards, but it's picky on what card you use.
Netkas in the Mac community is big on this, don't have a link to it but check his site out.