Sorry to open a thread for that question but I'm quite lost in all the details in threads relative to 10.8 or 10.9 on older mac. So I have a MacPro Rev1.1 with and Radon HD 5770. That 7 (or 8?) year config is still a monster running everything I install alas I feel more and more claustrophobic to be restricted to OSX 10.7.5 (and even XP). I was expecting MLPostFactor succeed release a new version but it seems not and then saw there are other way but can't find if any offer a solution for my config. So if someone could help.