With the notable exception of the video card.
What's up with that on the Mac Pro though? Do they use standard cards post-intel switch?
No. Before, you needed a special PPC ROM, since the PPC CPUs count to ten in a different way than x86 ones do. Now, you need an EFI ROM, since the x86 Macs don't use the traditional BIOS.
The other half of the answer: They've always used standard cards, you just needed to flash the PPC ROM image onto them. They work fine after that. You can reflash cards and put them into Intel Macs, too. Currently only the ATI X1900XT, NV 7600GT, and NV Quadro FX 4500 BIOSes are available, but there are some crazy/testicularly enhanced dudes out there reverse-engineering the naughty bits as we type. Soon enough you will be able to buy a Mac Pro and then buy an unGordly expensive 8800 Ultra for it as well. You'll flash the BIOS, plug it in, and watch your room lights dim.
Of course, Apple only has OSX drivers for the above-listed cards so far, so hopefully 10.5 will be launched at the same time as some new 8X00 powered Intel Macs.
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