I run a htpc with win7 already for couple of years without a hitch. Suddenly two days ago my Onkyo TX-875 doesn't pass through the hdmi video signal anymore. And even stranger: when I plug out the hdmi cable running from the Onkyo to the tv, the sound is will come through, although downsampled. But the moment I plug in the Tv again there's nothing. Even with simple pc sounds or avi's so it's not a DCHP problem. When I connect the htpc directly to a tv screen evererything comes through to, but I don't want, for obvious reasons, the sound processed by the tv.
So it's clearly something between the htpc and the onkyo.
But everything else, PS3, DVB-C work ok on every hdmi input on the Onkyo and that includes DCHP protected content.
So to summarize:
NOTHING was changed prior to these events.
All Sound AND video are not processed between htpc and onkyo
Sound only when I disconnect hdmi from TV, but then downsampled
Sony PS3 and DVB-T cable work ok with Okyo
Replaced DCHP compliant video card with a new one, no difference
Restored to an earlier restore point; no difference
Did a clean Win install; no difference
The only thing I can think of here is a mobo malfunction, so I ordered a new mobo.
For the rest I am clueless here.