I recently upgraded to Windows 7 on a Dell 545 MT with audio/video output via an NVIDIA 9800 GTX+ to a flat screen television.
I have installed/uninstalled/reinstalled all the recent drivers from NVIDIA and Realtek, but the machine will not recognize the HDMI output as a sound device (as it had previously in Vista). I troubleshooted the problem with Dell for over an hour and was then directed to their software specialists who want $130 to fix the issue!
Can anyone offer some insight into this? I've searched NVIDIA and Windows 7 forums without success and would really like to get sound coming back through my TV speakers.