I don't think the nvidia 8800 gs supports audio over HDMI, at least I don't see it as a spec listed on nvidia's site. You'll notice for the 9600, for example, that they list HDMI audio as a feature (though it's only passthru SPDIF).
For example, see this post on nvidia's forums:
http://forums.nvidia.com/lofiversion/index.php?t45880.html
I guess it's a good excuse to upgrade, if you really want audio over HDMI... but you can just run a separate audio cable too
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I have a Samsung LN-T4066F I hooked up a PC with a DVI port to HDMI port. I have no Audio, I have seen something about video cards putting out an audio signal and I have updated the Driver for the video card Nvidia GeForce 8800 GS. Any suggestions???? Thanks in advance

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