Does duplicating displays to 2 monitors (1 monitor off) increase GPU usage?

[tracerit]

I have a R9 270 with two displays connected to it (24" Viewsonic through DVI-D and a 55" Samsung TV through HDMI).

I've been using "Windows Key" + "P" to change displays but it seems the 55" TV is the primary and the 24" is the secondary which bugs me. So at this point i'm just thinking about duplicating the screens but if I turn the 55" TV off, will the GPU still try to render out to it?

 

[tolis626]

I have a R9 270 with two displays connected to it (24" Viewsonic through DVI-D and a 55" Samsung TV through HDMI).

I've been using "Windows Key" + "P" to change displays but it seems the 55" TV is the primary and the 24" is the secondary which bugs me. So at this point i'm just thinking about duplicating the screens but if I turn the 55" TV off, will the GPU still try to render out to it?

No need to duplicate it.I'm using a similar setup.Just open CCC and go to Desktop Management->Creating and arranging desktops and simply choose which screen is the primary and which is secondary.I think you can even simply drag the screen to the left to make it the primary one,but I'm not sure about that.

That said,I don't think duplicating will have a significant overhead.The image is rendered once and then just goes to different ports.In theory,there should be no performance hit.There's just no reason to do it so.

 

[tracerit]

used CCC and changed things and i thought it would work but when i go back to Windows Key + P it wouldn't trasnfer those settings over. Looks like CCC and Windows doens't share the same settings.

 

[tolis626]

used CCC and changed things and i thought it would work but when i go back to Windows Key + P it wouldn't trasnfer those settings over. Looks like CCC and Windows doens't share the same settings.

Oh,I just checked and scratch that part about dragging the screens in CCC.That's for Windows.Go to the resolution management screen and drag your monitor to the left there.That ought to do it.

 

[KingFatty]

used CCC and changed things and i thought it would work but when i go back to Windows Key + P it wouldn't trasnfer those settings over. Looks like CCC and Windows doens't share the same settings.

I'll confirm your experience is correct, and it's impossible to use software/driver settings to change which display is treated as the "first" when it comes to using the win+p shortcut.

My work-around has been to simply swap cables. My experience has been there is a hardware assignment here, and the hierarchy is assigned to the physical ports on the display. For you, it looks like the HDMI port has a higher priority than the DVI port. And my experience has been that the displayport has highest priority, if that helps. But hopefully both your displays have appropriate connectors so you can easily swap cables. Make sure the display you want to be number one will be plugged into the hardware port on the video card that has the higher priority than the display you want to be treated as secondary/number 2.

As for assigning which display is "primary" under the windows display settings, that is a separate issue that does not affect which display is first for the purposes of using the win+p shortcut to change multimonitor settings.

It's quite annoying that this cannot be changed and you need to resort to swapping cables around, but I just think the bug is a low priority item and not many people, if any, have reported it.

 

[ViRGE]

So at this point i'm just thinking about duplicating the screens but if I turn the 55" TV off, will the GPU still try to render out to it?

Probably not. Since the TV is HDMI, then the PC will usually detect that the display has been disconnected and remove it from the system accordingly.

That said,I don't think duplicating will have a significant overhead.The image is rendered once and then just goes to different ports.In theory,there should be no performance hit.There's just no reason to do it so.

I concur on this point.🙂

 

[KingFatty]

There is a chance that going multi-monitor will cause issues with memory speeds and flickering when switching between 2D or 3D etc. as the memory speed is changed etc. But that's a trivial increase in power.