Thanks for all that. It appears to be a kernel crash which at least indirectly looks related to the Nvidia driver version 390.
** Summary changed: - Screen freeze + [nvidia] Screen freeze ** Package changed: gnome-shell (Ubuntu) => nvidia-graphics-drivers-390 (Ubuntu) ** Changed in: nvidia-graphics-drivers-390 (Ubuntu) Status: Incomplete => New ** Also affects: linux-hwe-5.8 (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1933118 Title: [nvidia] Screen freeze To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-hwe-5.8/+bug/1933118/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs