I have a new build, fresh Windows 7 Pro install. All the latest drivers/BIOS. Running an i3-2120 chip, 8gb RAM. Mitsubishi WD-70635 DLP TV. If I boot up the PC with the TV switched to the HDMI connection I see the BIOS splash screen, then the TV goes blue until the Windows Desktop comes up. At this point everything is fine. I can get into Windows Media Center and watch live TV and recorded shows fine. The problem is if I change the TV over to another input and then try to switch back to the HDMI connection the PC is on, all I see if static or snow. It doesn't matter if I stay on the other input for 5 or 10 minutes or if I switch it immediatly back, the result is the same. Now if I get into the PC using VNC or Remote Desktop and change something on the graphics properties, all of a sudden I get a picture. I've also noticed if the computer display is powered down through power management and I switch to that HDMI connection on the TV, once I hit a key to take it out of display power down, the picture if fine as well. The intel software has the TV detected as Digital TV MEUSPTV10 and windows has it detected as Generic PNP Monitor.
I had an older computer running an e6400 chip and ATI HD5750 graphics card using the same HDMI cable and HDMI port and never had any problems with it.
I understand thatwhen you are using your TV as the display for your Intel(R) Desktop Board DH67BL it works fine but as soon as you change the source on your TV and then go back to the HDMI you wont get any display until you make a change in the graphics options.
In regards to your inquire, the Intel(R) graphics controllers will not force an output like some video cards, to send signal thru a port, the graphics controller needs to receive a signal to notify that a device is connected. Now, it seems like your TV is not sending this signal when you switch the source. Another possible cause is the signal detected by the graphics controller when you change the source is not fully compatible and it stops the signal. You can try installing the INF file from the TV manufacturer or the driver if they have one. This can only be provided by the TV manufacturer.
Thanks Victor. Of course there isn't a driver for my TV so I ran the moninfo.exe utility and create an inf file. Still same issue. I did find a utility that forces an HDMI resync with a hot-key so I will probably try that.