I recently upgraded to Windows 7 on a Dell 545 MT with audio/video output via nVidia 9800 GTX+ to a flat screen television. I have installed/uninstalled/reinstalled all the most recent drivers from nVidia & realtek, but the machine will not recognize the hdmi output as a sound device (as it did previously in Vista). I troubleshot 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 insights on this? I've searched nVidia and Windows 7 forums w/o success and would really like to get sound coming back through my tv speakers. Many Thanks.