I have a 2006 Apple Mac Pro 1,1 that I have upgraded the CPU's to 2x Intel Xeon X5355 SLAEG CPU's and upgraded the ram to 11GB. I have also flashed the firmware to the 2,1 firmware and installed Yosemite with SFOTT. I have also upgraded the Graphics card to a Zotac GTX 570 1280MB . I have been using it in this configuration without issues for a long time. Im just wondering is there anyway to flash the card to a mac compatible EFI and have working boot screens. also I'm using 2 monitors and would like to add a third what is my cheapest option. I do still have the stock NVIDIA GeForce 7300 GT. I am also trying to find the easiest way to upgrade to El Capitan on the Mac Pro.