Currently Being ModeratedNov 29, 2012 10:55 AM (in response to Stuart Jagoda)
One or two Apple-firmware 5770 cards can be used simultaneousy in a Mac Pro. It requires ONE Aux power cord for each card.
ONE Apple-Firmware 5870 can be used in a Mac Pro, as it requires TWO Aux power cords, and that is all that are available.
Please tell us more about what you are trying to accomplish, and you will get more help. Readers do not want to have to write a book-length answer to your overly-vague query.Mac Pro (Early 2009), Mac OS X (10.6.8), & Server, PPC, & AppleTalk Printers