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I am just getting started with my own server and thought I could put my old black macbook to some use.

I installed Ubuntu server 11.10 as the only operating system and everything has been working out well so far.

As expected the brightness keys don't work and closing the laptops lid does not put it to sleep or does anything.

As I only want to access the server remotely, I want to disable the screen to save power without having to rip it off.

So far I tried using vbetool and xset dpms in all variations.

echo $DISPLAY yields nothing so i think this is the problem.

When trying xset I get the following error:

xset: unable to open display ""

Me being not a linux pro I can only guess that I somehow have to give hi access to my display. Is this a driver issue?

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migrated from Jan 28 '12 at 12:01

This question came from our site for professional and enthusiast programmers.

Switch monitor off: vbetool dpms off

Turn it on again (keyboard don't do it): vbetool dpms on

Get from

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no, as stated above stops working after a few minutes – David Nathan Nov 29 '12 at 9:18
What do you mean by "stops working" ? – azat Nov 29 '12 at 10:52
Well, the commands do not turn the monitor on or off. They do a few minutes after startup, but then they stop working. Its strange – David Nathan May 14 '13 at 10:02

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