I have an NVidia GTX 1080 (8GB) Graphics card with 4 displays attached. For some of my games, I need to change resolution, which causes some weird issues with one of the secondary displays.

As a workaround, I tried setting that display to have it's own X screen in NVidia X Server settings, but now it only shows a black screen. When I move my mouse there, the cursor turns into a big X, so the screen is working, but there is no desktop/window manager there. Is there some extra step I need to take for this to work, or do I need to use a different Desktop Environment?

Linux distro is Kubuntu 19.04

Out of all of the available desktop environments, KDE seems to have the most issues with multiple displays.

I have an nvidia gtx 1080 and tesla k10 installed on a supermicro X9 board. I recently did a fresh install of Eoan Ermine. Then imported my .config and .kde directories. Got two 4k tvs for screens fully functional in two display ports. It worked well for a few days, but when I restarted, I suddenly had two black screens. The bottom screen/TV responded to right click. I was able to create another panel. When I tried adding widgets, it seemed to be aware of the widgets I'd previously installed.

The other display worked with only a mouse cursor and black screen. KDE's pager detected the top TV just fine, showed me a dialog box that was "hidden" by the black screen.

I moved .config and .kde into a temp folder, but no behavior changed.
I removed nvidia's maintainer 435 driver, installed from the latest .run from their site. Still nothing.

Logging in with gnome and xfce work perfectly fine with both displays.

xfce4 dropped their quicklaunch plugin.

There is some serious issues with multiple monitors. I have not played games for a while now, since I am busy updating my website.

However, a while ago I randomly investigated an issue related to widgets loosing their position after exiting full screen applications. I created a CLI script to automatically fix this displacement, found here: https://beamtic.com/kde-widgets-change-position

I am not sure it will work in your case, but I think the issue might be related. I am planning to update the script, using Python instead of PHP for the string replacement, as it will probably be installed on more systems.

A better solution would probably be to have an extra user that you use to play games with, and then don't mess with the resolution on your main profile at all.