I am using the Avid recommended nVidia 91.85 driver.  However, as I am trying to upgrade my system to do Blu-ray disc authoring, I am finding out the driver does not permit the playing of HD Blu-ray discs - at least with the Cyberlink player.  Cyberlink runs a compatibility check when the disc is played and finds it can't display HD and dumps out.   It then offerts to install the correct driver.

 Cyberlink's Power DVD Ultra does not play BD's from folders on your hard disk. This feature hed been deleted with the latest version of Power DVD. I contacted their technical service and they did not make their version available which included this feature - so I finally cancelled my download contract and got my money back.

In the roxio DVDit Pro HD user forum, others have reported that Power DVD Ultra even does not play back BD's placed in the local BD-player/recorder of the computer.

Another remark concerning nvidia drivers. I had the FX3400 installed with the latest driver 162.65 and it does not play BD's. I think, this is an issue of the FX3400 (and others) which do not support HDCP. I exchanged my FX3400 against a Sapphire 1950 Pro (ATI graphics processor) and it plays BD's now. However, the Open GL performance of this graphics board is by far worse compared to the FX3400.

Joachim