Disable Screensaver (Black Screen) in Ubuntu 12.04 (Precise Pangolin)
Is your desktop screen going dark or showing a blank screen when idled? By default, Ubuntu is developed with screensaver enabled. It is automatically activated when your computer becomes idled for roughly 5 minutes. When watching movies or online flash videos and the screensaver is activated, it darkens your display. If this is becoming a problem and you want to turn it off, then this brief tutorial is going to show you a single line command that will turn if off for you.
Objectives:
- Turn off screensaver in Ubuntu 12.04 (Precise Pangolin)
- Enjoy!
To get started, press Ctrl – Alt – T on your keyboard to open Terminal. When it opens, copy and paste the commands below, then press Enter to disable screensaver.
gsettings set org.gnome.desktop.screensaver idle-activation-enabled false
That’s it! Your display will never go dark or black again.
Enjoy!

Did not appear to have any effect in ubuntu. Screen turned off in five minutes after using this command.