Found this rather handy post that tells you what to do in newer versions of Gnome Power Manager, which for some reason hide the Do Nothing options as default.

Personally I find it irritating as the battery readout in all the distros of Linux I’ve used on my Eee report the battery at 0% over half an hour before the battery is actually dead.  No amount of conditioning or software modification seems to fix it, so I’m living with it.

However, with the newer versions of Gnome Power Manager, Do Nothing is hidden!  So my machine would go to sleep, despite the fact I know there’s at least 30 more minutes of battery life going to waste.  So annoying!

To fix it (albeit temporarily), you need to edit the gconf values for the settings you’re interested in to “nothing”.

The easiest way to do this is to use an application like gconf-editor and edit the values through that:

  1. Run gconf-editor.
    • If you don’t have it installed, go to your favourite package manager and install it through that.
  2. Using the column on the left side, navigate to apps > gnome-power-manager.
  3. In my case, I wanted to change the critical battery behaviour to Do Nothing.  So I navigated in to actions and set the value of critical_battery to nothing.
    • If you want to change, say, the behaviour of a power button press, navigate to buttons *instead of *actions.
    • Repeat this step for each value you want to change.
  4. Close gconf-editor.

That’s it!  One thing you need to keep in mind is that if you later change the setting away from Do Nothing to something else, the Do Nothing option will disappear.

Hope this works for you as it has me.

(I’m typing this post with 0% battery left!  What I crazy daredevil I am.)

Update 19:58: Forgot to mention that Do Nothing will disappear if deselected.  Fixed.