Noticed that when my Home Theater is off, the sound panel detects my TV, as soon as I turn it on it disappears. When I turn it off again the TV appears back. This is an Emotiva UMC-200 Home Theater Preceiver.
That whole setup worked fine with an Intel 2500T, Windows 7 and Gigabyte GA-Z68AP-D3 though, same cables: sound through HDMI into that Emotiva and image on the TV. Only the PC changed.