so, i installed OSX 10.8 and after the installation and reboot my nVidia Quadro 5000 was working!! my Mac Pro has a Quadro 4000 and 5000 installed, but i was only able to use the Quadro 4000 with OSX 10.7, and both worked in Windows 7. now i can use both Quadros with 10.8...holy cow, this is really cool!! 