I'm currently running Ubuntu 14.10 set to a resolution of 1920 x 1080, but on start up of the system, the resolution is incorrectly set to 3840 x 2160 (with no scaling) at the greeter screen. On subsequent accesses of the greeter screen by locking the system, the resolution is at the correctly set resolution of 1920 x 1080, but by logging out, the resolution reverts to 3840 x 2160.
I have noticed that there is another question addressing a similar issue but I'm not sure if the solutions apply to Ubuntu 14.10. Copying ~/.config/monitors.xml to /var/lib/lightdm/.config appeared to resolve the problem but the screen displayed the incorrect resolution briefly, before "flashing" and displaying the correct resolution.
