Note that not all X implementations are guaranteed to honor all of these options.
One last idea regarding this. If we leave the default setting alone it blanks at 10 minutes,
which is usually OK. Then we want to watch a movie, I can run "xset dpms 0 0 0" from the
terminal, a desktop icon, or an OpenBox menu item, and that command actually works on my
machine stopping the screen from going blank at 10 minutes. But, as you said, isn't working
from the autostart.sh file for some reason. Probably the easiest way to set it up on my
machine without the xscreensaver.