When using an AVR with an HTPC, there are several reasons that can make it necessary to connect the video card directly to the TV instead of going through an AVR. For audio, you can then use S/PDIF from the motherboard, and that works great, but you do sacrifice the lossless multichannel codecs. For the latter, you need to connect to the AVR with HDMI, and while it is possible to use a second video card port for this, it creates a "phantom" display in Windows, and more problematic, it isn't stable. As you switch inputs on the AVR and turn devices on and off, Windows will reconfigure the monitor arrangement, get wrong EDID and cripple the audio capabilities, and do stupid things like moving the desktop and whatnot.

What is needed is a way to configure an HDMI display as audio-only and always present with consistent and correct EDID. Is this possible now, and if not, could it be added? I wouldn't have thought so, but a couple of people have reported in other forums that this is possible with a competing product by using its "Ignore monitor" feature. (Links provided on request.) I see DisplayFusion has a feature by that name, but it doesn't do what I need. The only other option I see is to disable a display, but this disables the audio as well.

Apparently "ignoring" the display in UltraMon somehow leaves the HDMI connection alive for audio.

Start here and read the immediately following two messages for elaboration:

http://www.avsforum.com/forum/166-lcd-flat-panel-displays/1609066-lg-65ub9500-11.html#post31717025

I found out about it from DavidinCT's message:

http://www.thegreenbutton.tv/forums/viewtopic.php?p=85939#p85939

We talked about it and other possible approaches, and after a false start or two, here's his confirmation that UltraMon is working for him:

http://www.thegreenbutton.tv/forums/viewtopic.php?p=86522#p86522
http://www.thegreenbutton.tv/forums/viewtopic.php?p=87457#p87457

He says he did have to configure the TV as display #1 in Windows, which may be a limitation. I wouldn't want to make my TV my primary display. In fact that wouldn't be useful at all to me. Here's a little more about my setup. I have Intel 4600 graphics on an i5 4670, and I connect it to my monitor, the primary display. I have an Nvidia GT640 that I connect directly to my TV, and I extend the desktop to the TV. Connecting the TV directly to the card instead of going through the AVR keeps it alive in Windows at all times, and I have no power sequence or input cycling issues as I do when I connect video card to the AVR. I would like to set up an audio-only HDMI connection to the AVR using the second port on the Nvidia card.



The Pin 19 trick sort of works, but after using it a while on my gaming machine, I found that an Nvidia driver update sometime within the last year left Windows unable to detect the TV after being rebooted. I've also tried the Gefen HDMI Detective and found it unreliable with HDCP and Nvidia cards, a problem Gefen blames on Nvidia.

I'll check it out this weekend and let you know what I find.

I tried UltraMon, and it does mostly work to keep the mouse and windows off an ignored display. However, it's incomplete; for example, while I can't move the mouse onto an ignored display, I can drag a window fully onto it, and when I release the mouse, the cursor and window snap back to the primary display. The ignored display is present and active in both the Windows and Nvidia control panels. When I switch inputs on my AVR, Windows loses the ignored display completely, so UltraMon does nothing to keep the connection alive. As for EDID, I see no way that it helps with that; in fact, after some sequence of reboots, input switching, etc, Windows derped itself and left me with 2ch LPCM instead of the HDMI surround formats. UltraMon is not what I thought was being described in those threads I linked to. Sorry about the wild goose chase. I should have tested it myself first.

That said, if it's possible to create a feature to enable an always-present, constant EDID secondary display via software, it would be a holy grail for a lot of people. Expensive workarounds like HDMI Detective don't work properly with Nvidia cards due to HDCP incompatibilities, and free workarounds like the Pin 19 trick are very much YMMV.