Thanks. Yes the messages about "Memory pressure relief" sound unusual. I've never seen that before.
Don't worry about the inability to switch VTs. That's not part of the bug, that's just because switching VTs is the responsibility of the currently active display server. If Xorg has frozen then you also won't be able to switch VTs. Next, please monitor the memory usage of your processes before the next freeze happens, with something like: ps auxw --sort -rss | head so we can identify if and what is using too much memory. In case the issue is gnome-shell like it sounds, please also ensure you have uninstalled all third-party gnome-shell extensions except for the standard Ubuntu ones. ** Tags added: nvidia ** Summary changed: - Xorg freeze + [nvidia] System freeze ** Package changed: xorg-server (Ubuntu) => ubuntu -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1861043 Title: [nvidia] System freeze To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+bug/1861043/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs