I recently just got a Mac Pro 1,1 for free. It's the 2.66 dual cpu model with the Geforce 7300 and 1 GB of ram. It is currently running 10.6.8. I already have installed a SSD and have ordered 4 gb of ram which will bring it up to 5 GB total. I have two video cards sitting around that I would ideally like to use if possible. They are not mac cards. I have a ATI Radeon HD 6750 and a nVidia 8800 GTX. (I bought 2 6pin video card cables) From what I have been reading it sounds like once I get 10.7.5 on this computer nearly any video card will work, I just won't see the bootup screen. Then assuming I can get the video card's working I would like to update to a more modern OS. Bottom line I'd like to get this computer on Mavericks or better with either one of those listed video cards. Would this be possible?