Greetings. Just want to inform the MacRumors community that I have an EVGA Nvidia GeForce GTX 660 2GB (non-Ti model) running well in Mac OS X 10.8.2 Mountain Lion on a mac pro (my model is a 4,1 as the signature indicates), and I'm more than certain it'll work in any Mac Pro 3,1 and newer; However, this didn't happen without pulling teeth. I've searched all over Google, as well as Mac & Hackintosh forums to see if anyone got this working in the Mac Pro 3,1 and higher, but to no avail. I only ran into one article about the 660 Ti working, but that didn't help at all. Later, I accidentally found out that Apple recently released an exclusive 10.8.2 update for the new 2012 MacBook Pros and iMacs with GeForce GT/GTX 600 series GPU chipsets (Perhaps Apple will include such .kext files in the 10.8.3 update?) So I figured out how to extract the .kext files written for those chipsets, tested them after restart, and voila; The GTX 660 runs well in OS X, and is even recognized as such in the System Profiler! I tested this card with Batman Arkham Asylum on maximum settings, as well as X11, and they run very well. DVD player works, too. There are two known major drawbacks, though: The Mac Pro doesn't wake up from Sleep The Mac Pro may not shut down or restart properly Perhaps someone needs to write an efi.rom? If you don't want to wait for the (more than likely) 10.8.3 update, which should include the drivers, I am currently creating an installation package, and I will post it very soon. Also, I may post more updates before releasing the installation package. Even with the probable 10.8.3 update, it may give the same results unless Apple actually updates those drivers.