Solved "Clone Mode" with 2 separate resolutions?

One of my computers has a 1366x768 screen and is also attached to a 1920x1080 monitor.

I know this is possible because another computer I have works this way. Currently, there doesn't seem to be any special parameters in xorg.conf in either computer. The computer in question is running the "nvidia" driver. As it stands, the internal monitor shows a useless partially cut off screen.

I would like to switch my television input from my plasma tv to this monitor during a power failure because it is backed up by battery. This means I need the internal screen in the laptop to be usable as well.

How do I setup xorg to display the same thing in both monitors despite the differing resolutions?

I was mistaken about how this all works. The clone mode resolution apparently cannot be higher than the native resolution of the lower resolution monitor. I was able to use Nvidia Twinview to set both monitors to 1366x768 in clone mode which works for me.

edit 2:
The --scale-from option was what I was looking for. This fairly cleanly scales the smaller resolution monitor to match the larger one. Problem solved.
Last edited: