I found out nvidia_drm modeset parameter was not enabled correctly even if I enabled it in a/etc/modprode.d/ config file (options nvidia-drm modeset=1).
sudo cat /sys/module/nvidia_drm/parameters/modeset N But after adding nvidia_drm.modeset=1 to grub cmdline via /etc/default/grub, now nvidia_drm.modeset is correctly enabled. And now I can use fractional scaling (125%, 150%, 175%). But still affected by https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/1825593 and https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1852860 Ubuntu 20.04 LTS GeForce GTX 1050 Mobile Dell XPS 9560 nvidia-driver-440 (440.82+really.440.64-0ubuntu6) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1870736 Title: [nvidia] Screen scaling 125% gives 200% To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-control-center/+bug/1870736/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs