Also, do not forget to exit the tty1 session, since you can go there even though your screen may be locked. I personally use this line:
sudo killall -9 lightdm; sudo service lightdm start && exit -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1070150 Title: Intermittent low graphics mode with Intel HD graphics To manage notifications about this bug go to: https://bugs.launchpad.net/lightdm/+bug/1070150/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs