Screen tearing and graphical problems with extended display using HDMI sound out to receiver

mof · 2 Feb 2016 at 23:04

I wasn't sure which forum to post this in.
I have audio going from my graphics cards HDMI out to my A/V receiver. To get this to work in Windows 7 my AVR is detected as a display so I've had to extend that display even though I only have one actual monitor. My monitor is connected to the graphics card by display port (I don't use HDMI because it limits the refresh rate to 30Hz @ 2160p).

When I watch some videos online and when I play games I will get screen tearing despite v-sync being on. The image has other lines that shouldn't be there and generally doesn't look right.

As soon as I turn my AVR off and my PC goes back to just using one display, all the screen tearing and graphical errors go away and the game/video looks perfect.

Something about extending the displays is causing a problem. I noticed that the AVR was set to 2160p 30Hz so I changed it to 1080p 60Hz so that the refresh rate of both displays would be the same but that didn't help.

Is there a way of getting just audio over HDMI from a graphics card (or sound card) without having to treat it as another display device?
Maybe there is something I can change in the Nvidia control panel?
Perhaps this works better on Windows 10?

Aberfala · 3 Feb 2016 at 08:05

mof said:
Is there a way of getting just audio over HDMI from a graphics card (or sound card) without having to treat it as another display device?

Unfortunately not.

I had a similar setup to you but in the end I gave up using HDMI for audio.

Radox-0 · 3 Feb 2016 at 09:31

There is not sadly, or at least I do not believe there is. Have a similar setup with Audio via HDMI and the Display Via DP 1.2 as its 3440 x 1440 and only has HDMI 1.4 (on the monitor) thus limited to 50hz via HDMI and also on Win 10 (No difference)

I once saw the random second monitor and deleted it not knowing what it was. A few hours later I deleted after restarting my PC, I could not get audio and did not link it to the second "Shadow" monitor being needed for HDMI Audio and only found out as such when I visited the various threads on the Nvidia forum. Once I recreated the second phantom monitor again it worked fine.

I do not seem to be getting too much or any worse tearing thanks to using this method and having just had a peek, my settings for the second monitor is 1280 x 720 with the setting set to extend these displays.

Jamesyboyjim · 3 Feb 2016 at 09:35

Set your card to duplicate display rather than extend desktop, then set your monitor to the primary display. This should eliminate the screen tearing on your monitor. I'm not sure where the setting is on NVidia drivers but I've had to do this on all my amd cards on every windows version since vista!.

mof · 3 Feb 2016 at 09:47

Thanks for the replies. I didn't think there was a way round it.
I've read that using different types of connectors can cause tearing with extended displays (e.g HDMI and Displayport) even when the monitors are identical.
I'm hoping there will be an adapter that will let me have one cable going from the pc to the AVR carrying both audio and video @2160p 60Hz - DP 1.2 to HDMI 2.0 - but I don't know if it will be possible.
There are already HDMI 2.0 to DP 1.2 adapters which might help with the multiple displays problem.

mof · 3 Feb 2016 at 10:08

Jamesyboyjim said:
Set your card to duplicate display rather than extend desktop, then set your monitor to the primary display. This should eliminate the screen tearing on your monitor. I'm not sure where the setting is on NVidia drivers but I've had to do this on all my amd cards on every windows version since vista!.

I've just tried duplicating the display and it's working. I'm playing the Witness and the sound is working and there's problem with the picture. Thanks Jamesyboyjim.

I noticed that when I changed the source of my monitor to the HDMI input I could see the game on there too. If duplicating the display is sending out two video signals when you're playing a full screen game will it affect the performance?

EDIT: Rise of the Tomb Raider doesn't seem any different with duplicate displays. I didn't do a thorough test comparing frames per second. I'll see if I notice anything in other games.

Jamesyboyjim · 3 Feb 2016 at 10:21

mof said:
I've just tried duplicating the display and it's working. I'm playing the Witness and the sound is working and there's problem with the picture. Thanks Jamesyboyjim.

I noticed that when I changed the source of my monitor to the HDMI input I could see the game on there too. If duplicating the display is sending out two video signals when you're playing a full screen game will it affect the performance?

Glad its working for you, it took me a while to solve when I ran into it!

I'd imagine the card is working harder pushing out the video to two displays but as its not having to render two different images the performance hit shouldn't be too bad.

I don't know the answer for sure but from personal experience I've never noticed any difference and my card is an old amd 7950 so playing newer games like GTAV etc pushes the card but it never drops more frames with two duplicate displays than with one screen.