System: Dell XPS600 3.0 Ghz Pent D / 2GB RAM / Dell installed Roxio MYDVD LE and Cineplayer
I recently had to replace my factory installed Nvidia 7900GS video card. I bought an 8600GTS to replace it. I had installed it and it seemed to be working great for weeks now. Then I tried to play a DVD. Every time the player would try to start the DVD I would get the dreaded Blue Screen of Death with reference to the file Nv4_disp.dll. It didnt matter if I used the Cineplayer or Mediaplayer, results were the same.
I did some research on the net for the issue and found lots of people were having this same error in games but could only find one who was having a DVD playing issue. None of the info I found had any solutions. I did find some reference to the newer card having some kind of hardware video enhancement called PureVideo and that it had conflicts with software DVD players. I could find no way to disable this on the video card.
I tried rolling back drivers etc, etc but was getting nowhere. Finally by pure accident I launched the Cineplayer software with no DVD in the Drive and looked at the DVD settings menu (Settings - DVD - Video) and there was a selection for Hardware Acceleration (DXVA). It was set to "Use if Available". Either my old 7900GS card had compatible hardware acceleration or it had none at all. I turned this option to off and was able to play DVD's once again.
Thought I would pass this along to anyone having the same issue.