I had this problem repeat. A GDM restart isn't required to fix this. I dropped into a console and just set the resolution to 1680x1050 manually using xrandr and it comes back fine.
Still a bug that it happens in the first place! -- Screen randomly blanks with a "not optimum mode" monitor message https://bugs.launchpad.net/bugs/548956 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
