You may have noticed the blanking of screen after an idle timeout. This may be annoying while you are watching a movie. So If you want to disable the X screen blanking that comes up unexpectedly while you’re watching a movie in MPlayer or …,
Type this at terminal
setterm -powersave off -blank 0
To make the change permanent, add the following to your ~/.xinitrc file:
$ vi .xinitrc
add this line
setterm -blank 0 -powersave off -powerdown 0 xset s off