X Display Manipulation

Rotate Screen

Try:

$ xrandr -o left

To have it initialize when X starts, you could try putting that line in /etc/gdm/Init/Default

Dual-head Displays

If for some reason your dual-head configuration isn't being saved properly, you can use xrandr to adjust the screens as part of a login-script.

Something along the lines of:

# xrandr --output DVI-1-0 --mode 1920x1080 --primary \
         --output DisplayPort-1-2 --mode 1920x1080 --right-of DVI-1-0 \
         --output HDMI1 --mode 1920x1080 --same-as DisplayPort-1-2

Turn On / Off Screen

To turn on:

$ xset dpms force on

To turn off:

$ xset dpms force off