I have a dual monitor setup at home, where the second monitor is connected through a surround sound receiver via HDMI. The main monitor is hooked up to a dedicated GPU via DVI, for 144Hz support. This ensure that I always get HDMI audio and all the HD-audio options that has, and at the same time full 144Hz frequency on main monitor for gaming. When the second monitor is turned of, the HDMI output simply identifies my receiver as a "monitor". When I'm actuall sending audio through the HDMI everything is fine, but when it's just passive it keeps dropping the PCM stream over and over (only for a second or so each time), causing my receiver to keep blinking and changing info on its front display. Not sure if this can be bad in the long run, but it's at least very annoying.
I have also had the HDMI setup through the same Nvidia card as my main display instead, and that works perfect, except for the fact that the card always run a high clock speed and draws a lot more power and gets warmer than it should in idle, as it clocks up when in multi-monitor mode.
Why is the HDMI output from the integrated Intel HD graphics on my MB dropping the non-active bit-stream, and can anything be done about it? Seems like the smarter option to have the second display, that is usually not even on, and only passes on the HDMI audio - on the integrated, and let the Nvidia card focus on my single gaming monitor, and clock down when idle.
This is all a very inconvenient solution but it is still the only one since no software or hardware options exist to this day where a modern high-frequency (or G-Sync etc) monitor can be used at the same time as full digital audio (only available with HDMI still) without stupid half-solutions like this. I have tried everything else, and nothing exists, trust me. Optical/coax audio? Fine for non-HD, can't output PCM multi-channel for games or HD-formats from BluRay. "Real time" encoding game-audio with DD Live or similar and output over optical exists, but the delay is very real (makes everything feel like it is out of sync), and it has a whole other side of issues with buggy support in some games etc. Analogue multi-channel output is the worst (and oldest) since the electrical interference (noise) from inside a PC getting to a high quality receiver and speakers will sound terrible. Sounds like squealing pigs when the PC is under load.
So, HDMI audio is the only real option today, being the only working digital one. And since HDMI is far outdated when it comes to gaming-tech monitors, this is what we get. Either you get good audio, OR you get a good gaming monitor working as it should. Not both without a lot of pain.