So I know the TX-SR606 has been plagued by a bad HDMI board in the past, and that you had to get the warranty work done to get it to be (somewhat) reliable. But I did all that. This thread is more about weirdness that happened just recently.
As of Monday night, suddenly my Onkyo won't pass video from my HTPC to my TV. It will pass audio for the HTPC. It will also pass video during the BIOS, but once I boot into Windows, no luck. Other monitors work fine, direct connection to the TV is fine. Other HDMI sources through the receiver are fine, it's like something flipped at switch that said "NO HTPC output for you!" In the short term, I'm bypassing the issue with a SPDIF cable and direct video to the TV. But I just thought it was odd, and wanted to share the experience with you guys.