How to make "xset s off" survive a reboot (12.04)

Just add it to your .xsessionrc or .xinitrc file.

This behavior is initiated at login and overrides the command if run at boot. To make this permanent, just add the lines below to the end of the .profile in your Home folder.

# Turn off screen blanking
xset s off && xset -dpms

If you don't see .profile, open your Home folder in your file browser, click on 'View' and select 'Show Hidden Files'. Then just right click on .profile, select 'Open with text editor', copy and paste the above on a blank line at the end of the file and save the modified file.