"screens go black" reminds me of bug 1873403 which might be somehow related.
** Summary changed: - cannot change main monitor after setting scaling for monitors w/nvidia drivers + [nvidia] cannot change main monitor after setting scaling for monitors -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-control-center in Ubuntu. https://bugs.launchpad.net/bugs/1873266 Title: [nvidia] cannot change main monitor after setting scaling for monitors Status in gnome-control-center package in Ubuntu: Incomplete Status in mutter package in Ubuntu: Incomplete Status in nvidia-graphics-drivers-440 package in Ubuntu: Incomplete Bug description: After booting with nvidia drivers, if I change which monitor is the main one first, then change the scaling from 100% to 200%, it works. But doing this in the inverse direction, by first setting the scaling and then changing the main monitor, it fails and the screens go black. Oddly enough, it also fails to revert this setting and I have to hard- reboot (though I could probably try switching ttys, etc). This is with focal and focal-proposed enabled. I also have the proprietary 440 nvidia drivers enabled, and I'm using default gnome with x11. --- ProblemType: Bug ApportVersion: 2.20.11-0ubuntu27 Architecture: amd64 CasperMD5CheckResult: skip CurrentDesktop: ubuntu:GNOME DistroRelease: Ubuntu 20.04 InstallationDate: Installed on 2019-07-05 (287 days ago) InstallationMedia: Ubuntu 19.04 "Disco Dingo" - Release amd64 (20190416) NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair nvidia_modeset nvidia Package: nvidia-graphics-drivers-440 PackageArchitecture: amd64 ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/bash ProcVersionSignature: Ubuntu 5.4.0-24.28-generic 5.4.30 Tags: focal package-from-proposed Uname: Linux 5.4.0-24-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip docker kvm libvirt lpadmin lxd plugdev sambashare sudo _MarkForUpload: True To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-control-center/+bug/1873266/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
