How can I actually change my "Power Management" settings?

I go into settings -> Power Management, trying to change the "Put display to sleep when inactive for:" and "Dim display when idle" settings. The changed settings are saved -- if I come back to the same menu, they appear as I left them.

But when I watch a full screen video, the display does get dim every once in a while. And if I leave my laptop alone for 15 minutes, the screen does go black (and lock itself).

How can I actually change these settings? I would also want to stop it from locking itself every time it went inactive -- just blank the screen.

Solution 1:

Workaround

Caffeine is a program that does what you want power management to-do.

You can install caffeine by adding the ppa. you can do that in

System --> administration --> Update manager --> settings --> then tap the "other sources" tab --> add

ppa:caffeine-developers/ppa

And now press the reload button.

or you can do it in a terminal:

sudo apt-add-repository ppa:caffeine-developers/ppa
sudo apt-get update

Then install caffeine by typing in a terminal:

sudo apt-get install caffeine

Power mangament

But you could also try to set the Power management settings as system default by pressing "make default", that worked for me in 11.04 and 10.04.1.

Solution 2:

You said after "15 minutes the screen does go black," so it sounds to me like you're looking for the screen settings:

To get there, go to System Settings and click on Screen. That's where you can change whether your monitor dims, and whether the screen turns off after a given duration.