I'm running Windows 7 with Sapphire Radeon 6850 card to Onkyo SR606 receiver outputting to Samsung UN46D6000 LED TV. I recently replaced the video card with the same model because the old one died, so I'm guessing the issue is some setting I've missed. Anyway, when I boot up the machine the receiver does not see any signal from the pc. I have to turn the receiver off and on a few times before it will see the pc. I've tried turning on the components in different orders, waiting a bit before turning on components, looked through all display settings on windows and ATI Catalyst Control center, I'm at a loss here.
When two components are connected with HDMI they perform a handshake looking for devices when powering up. That's why the order you turn things on can make a difference. I would make sure the PC is fully booted up before turning on the receiver.
You can try a different HDMI cable (shorter is better) or try changing the input and returning to the PC input of the receiver.
The voltage that performs this function is critical so even .1v difference can cause a royal pain. The 2nd board may be just a little lower in voltage than the old one.
I haven't had any luck resolving this issue, but I have found a way to make it work (sort of). I have to turn on the receiver and TV and wait a few minutes, then turn on the pc. Most of the time the receiver will see the pc immediately when I do this. Still a pain though. I've tried several different inputs on the receiver and they all act the same. Also, I've tested the HDMI cables and they're all functioning correctly. I guess I will try contacting Onkyo support if I get desperate. Thanks
After some searching I've found that this a common issue with this particular model Onkyo. Contacted them and they agreed to repair the unit for free even though it's outside of warranty range. I just pay the cost of shipping to their service center.