Ask Ubuntu is a question and answer site for Ubuntu users and developers. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

My OS is Lubuntu 13.04. After 10 mins of inactivity the screen goes black. What I did to stop it without effect:

  • uninstalled xscreensaver completely
  • in power setting I set to never blank the screen
  • run some command found in the internet with "xset" which was said to solve it (but maybe it was wrong command, if you know proper please write it)

And still nothing. I don't know why lubuntu wants so hard to keep going black when watching films. For example on kubuntu/ubuntu I just set in power settings to never go black and it works. Maybe lubuntu uses customized kernel with hard-coded extreme energy savings that can't be turned off?

share|improve this question
See my solution here:… – Magno C Oct 9 '13 at 18:38
I can confirm this behaviour for Ubuntu 14.04 after Upgrade from 13.04. The trick by TenPlus1 is working for me. – user273218 Apr 24 '14 at 9:44

11 Answers 11

up vote 7 down vote accepted

Try installing :

sudo apt-get install xfce4-power-manager

then configure it in:

share|improve this answer
Why you think he should install xfce4-power-manager? – Braiam Feb 13 '14 at 2:28
it works for me. Easy and simple solution. – Arturo Veras Feb 13 '14 at 2:35
On ubuntu 14.04 this doesn't work – Ghita Jan 2 '15 at 18:27

In Lubuntu it is an option in preferences called "Light Lock". It's annoyingly on by default.

share|improve this answer
I believe this is the correct answer. But I recommend expanding this to explain exactly where to find that, perhaps even with a screenshot. – Eliah Kagan Aug 22 '14 at 22:07
This is the correct answer for sure. I've found this in Main menu button (on panel)-> Preferences >> Light Locker Settings – JohnPoison Mar 15 '15 at 19:31

For a temporary fix pop into terminal and type:

xset s 0 0

and this should stop the 10 minute blanking problem, to make it more permanent, insert a line with the same command at the start of the /home/username/.profile file.

share|improve this answer
why is it temporary solution? Is it like running this command disables the blanking only for current session? – user1873947 May 5 '13 at 21:42
Or xset s off – qed Nov 9 '13 at 19:54
You can always disable Energy Star features: xset -dpms – swietyy Oct 1 '14 at 21:04

Helps for me after reboot. In /etc/X11/xorg.conf (if you not have it just create):

Section "Monitor"
    Identifier "eDP0" <<< or LVDS0 or VGA0 or ...
    Option "DPMS" "false"

Section "ServerLayout"
    Identifier "ServerLayout0"
    Option "StandbyTime" "0"
    Option "SuspendTime" "0"
    Option "OffTime" "0"
share|improve this answer
the only one that worked for me after updating my 14.04. thx. – smertrios Jul 27 '15 at 21:57

In Light Locker, just move the arrow in "Blank screen after" as far to the right as possible.

share|improve this answer

In Ubuntu Mate 15.10 x64, I had the same issue. In the upper corner of Mate, Go to System > Administration, then to LightDM GTK+ Greeter Settings and enter your password. In the next window, click upper right on Misc., there you will find Timeout Until The Screen Blanks and it will be set at 1 Minute by default. Just move the slider to the left to Never. This may also be the case in Lubuntu, but it was definitely the issue in Mate 15.10.

share|improve this answer

I eventually solved this issue in Xubuntu 14.04 by removing the packages

xfce4-power-manager and light-locker

sudo apt-get remove xfce4-power-manager
sudo apt-get remove light-locker

Whith xfce4-power-manager running, the monitor would not turn back on

Running light-locker in terminal resulted in this exception

EDIT: This still does not fix the problem, I am using proprietary Nvidia drivers

share|improve this answer

I believe I've found a solution to this problem. I've recently update from Ubuntu Mate 15.04, in which the black screen made me crazy, to 15.10, with a new installation. With the new version, after I set it up the screensaver off, everything seemed to work fine, no black screen at all. After that, I made a few customizations of the system, the last one of which was to delete from the startup applications, the power manager (I use a desktop pc so I thought that was a useless waste of time to run it). After that, and after a reboot, the hated black screen shown itself again. So I created a new startup application named Power manager and I set "mate-power-manager" as command. This simply solution worked for me and I believe that I got the problem in 15.04 for the same reason. Hope this helps.

share|improve this answer
Welcome to Ask Ubuntu! I recommend editing this answer to expand it with specific details about how to do this. (See also How do I write a good answer? for general advice about what sorts of answers are considered most valuable on Ask Ubuntu.) – David Foerster Jan 10 at 12:32

While viewing videos on my htpc, the screen would blank after 10 minutes with no keyboard/mouse input. Obviously not desirable behaviour for an htpc. Turning off screensavers and power saving did not have any effect. Eventually, my web searches led me to believe this was caused by the xserver. I tested this by running the following:

xset s off && xset -dpms

in a terminal at the beginning of a session and confirmed that this did eliminate the undesired screen blanking. Running xset -q in the terminal confirms DPMS (Energy Star) was disabled.

In order to avoid having to open a terminal and run this command at the start of each session, I set this to run at system boot. The screen blanking was back and xset -q showed DPMS enabled. Further searching revealed this behaviour is initiated at login and overrides the command run at boot. To run this automatically, 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.

share|improve this answer

new versions of Ubuntu is using gnome-screensaver, not xscreensaver. The settings is in System Settings -> Brightness and Lock

share|improve this answer
not true for lubuntu. – user1873947 Jun 24 '13 at 14:39
This is the best answer for ubuntu 14.04 – ton Apr 10 at 11:35

Installing xfce4 to avoid turning the screen black? That's ridiculous. You could try at least this simple script before insalling a complete desktop manager just for the screensaver (which turns on when you don't use the computer):

share|improve this answer
A simple drop link will not suffice. Explain why this is good, explain what to do. How do I install this, via apt-get or software center? Do I need Automake or can I just use make? – Virusboy Feb 17 '15 at 18:10
I mean this set of commands: xset s on xset -dpms xset s 120 xset s blank – David Vartanian Feb 19 '15 at 13:13

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.