Ubuntu
gnome-power-manager package

  1. Bug #447728
  2. Comment #17

Comment 17 for bug 447728

Revision history for this message
Nikil Mehta (nikil.mehta) wrote : Re: [Lucid] Laptop only remains DPMS off for 2 seconds

1. This problem still exists.

2. It appears that the origin of the problem is gnome-screensaver. By either inhibiting the screensaver (gnome-screensaver -i) or outright removing the gnome-screensaver package, this problem goes away. Why that is, I have no idea. Monitoring dbus after issuing 'xset dpms force off', a couple of screensaver related messages pop up:

method call sender=:1.10 -> dest=org.gnome.ScreenSaver serial=3223 path=/; interface=org.gnome.ScreenSaver; member=UnThrottle
   uint32 2035929630

and

method call sender=:1.10 -> dest=org.gnome.ScreenSaver serial=3300 path=/; interface=org.gnome.ScreenSaver; member=Throttle
   string "Power screensaver"
   string "Display DPMS activated"

Because the monitor is off I can't tell exactly when the messages arrive (and thus which message correlates to the backlight coming back on), but I would bet one of these points the way to the source of the problem. The documentation for Throttle/UnThrottle isn't exactly clear, but I would think a developer might be able to track down the issue, if they were so motivated.