Indeed. The log file does not list intel_drv.so, so maybe Xorg has to be explicitly configured to do so.
Here is an upstream bug report which appears be closely related to the blanking problem: https://bugs.freedesktop.org/show_bug.cgi?id=108021 ** Bug watch added: freedesktop.org Bugzilla #108021 https://bugs.freedesktop.org/show_bug.cgi?id=108021 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1801609 Title: Fails to deactivate dpms off mode after user initiated wake-up events(not system-suspended, just locked and dpms active) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1801609/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs