Okay, so now looking back at this bug, I see that when I have Focal with X11 and the 440 nvidia drivers enabled, I can set scaling to integer multiples without problems, but enabling fractional scaling and then using a fractional scaling results in the black screen problem mentioned in this bug as well as this in the system journal:
gnome-control-c[6913]: Config not applicable: GDBus.Error:org.freedesktop.DBus.Error.InvalidArgs: Logical monitors overlap ** Summary changed: - [nvidia] all monitor scaling fails due to overlapping monitors + [nvidia] fractional monitor scaling fails due to overlapping monitors -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to mutter in Ubuntu. https://bugs.launchpad.net/bugs/1869042 Title: [nvidia] fractional monitor scaling fails due to overlapping monitors Status in mutter package in Ubuntu: New Bug description: After an upgrade with focal-proposed this morning, I am unable to set any scaling for any of my monitors without the monitor turning blank for 15 seconds and reverting to 100% scaling. I am using X11 with gnome and proprietary nvidia drivers on Focal. I have 3 monitors attached, all 4K, and my usual setup is to enable fractional scaling, and set all 3 monitors to 150% scaling. Now however, I cannot change the monitors to use any scaling, and even if I disconnect 2 of the monitors to only have a single monitor I still cannot use scaling. Finally note I am just using the Settings window, I haven't fiddled with xrandr at all manually. ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: mutter 3.36.0-2ubuntu1 ProcVersionSignature: Ubuntu 5.4.0-20.24-generic 5.4.27 Uname: Linux 5.4.0-20-generic x86_64 NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair nvidia_modeset nvidia ApportVersion: 2.20.11-0ubuntu21 Architecture: amd64 CurrentDesktop: ubuntu:GNOME Date: Wed Mar 25 11:24:05 2020 InstallationDate: Installed on 2019-07-05 (264 days ago) InstallationMedia: Ubuntu 19.04 "Disco Dingo" - Release amd64 (20190416) ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/bash SourcePackage: mutter UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/1869042/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
