Is your screen saver switching off your monitor every 10 min?
Follow the next steps:

1) Install xScreenSaver.

use the following command  in a terminal:

     sudo apt-get install xscreensaver

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2) Disable the standard power management .

The following image is from LUBUNTU:

click on the menu Preference \ Default applications for LXSession


In Running applications at Power Manager select “no” and click Apply. Without Apply is not saving the changes


3) Add the screensaver daemon in the autorun.

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At the Autostart tab paste the following command and click Add.

     xscreensaver -no-splash


 4) Disable xScreenSaver.

click on the menu Preference \ Screensaver


Change the Mode to “Disable Screen Saver”