HI, I have a Mac Pro 1.1 with OSX Lion 10.7.5 with nvidia driver 295.00.05f03 installed. I tried the Forsa GT640 and it didn't work. I got the apple sound on boot but it stayed black for like 10 min. tried it three times no display. I thinnk the Problem was cause its a keplar car. But so far as I understand keplar drivers are in the 10.7.5 update and I installed the Nvidia drivers. Which Non EFI card is suitable or can someone help me with a list of keplar/fermi cards that work. I wanted the card for cuda acceleration in CS5 as the donkey's years old x1900 is just not cutting it anymore. Please keep that in mind. Thank you.