The price for Windows 4870 cards is substantially lower than Apple’s.
The Canada Apple Store currently
lists one for $420,
Canada Computers has one for $210.
this MacRumors forum thread
people are discussing how to do this and what the pitfalls are.
One person said:
I should note that doing this seems to make the analog output (SVGA) not work. DVI is fine, though one person reported the “top” port as only going up to 1024×768. Be careful out there. Read the thread for info on which cards work, and what possible side effects there are. YMMV. Reid
I just tried it on my Sapphire HD4870 (the 1st gen one, based onI flashed using freedos and the following command line:
ATI’s ref design).
atiflash.exe -p -fs -fp 0 4870.rom
note: -fs and -fp are used to ignore SSID and P/N mismatches And it works! EFI driver is initialized correctly, (I don’t have the leaked MacOSX
drivers for this card, so I can’t tell if this one works too), and
bootcamp stil works (currently writing from GNU/Linux on my 2006 Mac
Pro). Only problem is : only one output is active, no dual-head, it seems
(at least using ATI’s linux driver)