I usually run in Arch Linux with no issue, but today I restarted in Windows and I all got was a Black Screen.
After many attempts I realized that when my Radeon HDMI is connected to the Denon 1712 AVR I get a black screen but when it is hooked to the TV directly it is all good...
I do not have that issue in Arch Linux and I did not have it either with my previous AVR (a HK) in Windows.
Also it works fine in safe mode, and in normal windows mode if I uninstall the driver, so it has to be related to it somehow.
I tried installing an EDID inf file from there with no success:http://www.avsforum.com/avs-vb/showthread.php?t=1227161
I've tried pressing win+p and then switching output, having the Catalyst panel open, changing resolution as low as 800x600 (can't seem to get lower).
edit: Plugging the HDMI cable in Game 2 or AUX works fine, not any other port... weird...