News for Sunday, 10 September 2006

With the new Mac Pro, its PCI Express slots, and Bootcamp, many users might be tempted to use PC graphic cards in a Mac. Of course, the Mac Pro being freshly released, not many users have been trying to perform such operation yet.
First, graphic cards that can be installed in a Mac Pro have a special firmware supporting both EFI and BIOS. So, one could install them very easily in a PC, and it would work without problem. The reverse operation would not work straight; in a Mac Pro the graphic card must have an EFI-compatible firmware and Mac drivers should be available.
Only the GeForce 7300 GT, ATI X1900 XT and Quadro FX4500 are available as BTO for the Mac Pro, so drivers for those 3 cards are available. Some users have successfully installed a nVidia GeForce 7800 GT in a Mac Pro, while this card is not officially supported; but as it resembles (hardware level) the Quadro FX4500, one can assume that FX4500 drivers are compatible with the 7800GT ones.
To modify a firmware, one needs more tools and information. PC graphic cards are currently not compatible with EFI (it will come when VIsta will be released). To flash a PC card one will also need to get a EFI Mac firmware. In addition the ROM is different between PC and Mac graphic cards; from the GeForce 7300GT, Mac cards have a 128k ROM, instead of a 64k ROM for a PC card. So one will have to find a PC card with a compatible ROM size before being able to try flashing it.
What can we do without a Mac firmware? Not much so far. Some have tried to install a nVidia GeForce 7800 GT to replace the original 7300 GT. If you do so, the Mac will boot without anything displayed up to the time the GeForce 7300 GT driver is loaded. After that, the 7800 GT is working perfectly.
So there are plenty of possibilities to be explored, and we will start very soon. Indeed, we now have additional drivers available, the ones for the Radeon X1900 XT and the GF 7600 GT found in the new iMac. So, time for graphic cards "bidouille" is back. :)