I have a Mac Pro 1,1 which is in dire need of an upgrade, but there's no point doing that right now, with a (hopefully) imminent refresh on its way. I've been replacing what parts I can to improve the overall performance of the system, such as installing SSDs (which is actually proving to be a bit pointless as the disk speed seems to be limited by the SATA throughput on the motherboard anyway). I'm now turning my attention to the graphics board. Currently I have an 8800 GT that I got from ebay and flashed to an EFI32 ROM, which has been working perfectly. But now I want to update this with something a bit more meaty. I understand I'd probably need to keep the 8800GT as a "helper" card, which is fine (I have have a secondary display anyway). But what I wanted to know is, what is the highest-spec _nvidia_ card that I could put into this model and for it to work with Lion 10.7.2+ and Boot Camp? And if someone could point me towards a guide for doing so, that would be great too.