Hi everyone I have been trying for a month now yo install 10.10 on my mac pro 1,1 2.66ghz. I have purchased a non apple 8800gt card which shows up in system profiler for 10.7 and works just fine except no boot screens. However I am having issues with my Yosemite install. I tried the SFOTT install and my usb's from my cinema display stop working and my keyboard isn't working no matter where I plug it in. Also, when I tried a precompiled osx installer The mouse barely tracks and is choppy and again the keyboard doesn't work. I have tried other usb ports and all to the same effect. Is there something I can do?