FeatureDisplaySwitching

From cchtml.com

The Proprietary Driver supports runtime display switching.

To list displays that are connected

$ aticonfig --query-monitor
  Connected monitors: lvds, tmds1
  Enabled monitors: lvds

To switch between different display outputs (to enable the Laptop LCD and DVI LCD as above).

$ aticonfig --enable-monitor=lvds,tmds1
Using /etc/X11/xorg.conf

To allow the driver to find an enable displays automatically.

$ aticonfig --enable-monitor=auto
Using /etc/X11/xorg.conf