Comment 12 for bug 988290

I agree it's got to be somewhere else. It would appear that it is not hardware specific, not video card, nor monitor, nor kvm.

I just did a test from another machine to see if it's related to the gnome-screensaver, not sure if it's truly testing anything... :
0) switch to another machine on the kvm
1) login via ssh from another machine on the kvm
2) export DISPLAY=192.168.2.4:0 # IP of ubuntu machine having resolution issues
3) gnome-screensaver-command -a
4) switch back to ubuntu machine having resolution issues
5) verify screen is black/asleep and move mouse
6) resolution stayed at the proper 1920x1080

I've mapped a keyboard shortcut to run xrandr in the meantime :(

Hope this helps,
Dan