Ever since the Nvidia version 9.x.x.x drivers have come out, I have been unable to upgrade. Everything would work fine EXCEPT playing videos (in Nero Showtime, Media Player, Media Player Classic, anything) would have audio but video out be a blank green screen.
It took a lot of digging but the solution, at least for me, was to install NVTweak and enable VMR (which I don't know what it is). One enabled, video now play. Thought you guys would like to know..... Steve