Judging by upstream design documents[1], this feature has been changed by the GNOME folks to only dim the screen when idle on battery power. The tickbox for "Dim screen to save power" in the "Brightness and Lock" capplet in Gnome Control Center toggles the "idle-dim-battery" GSettings key, and on battery power your screen should dim after (by default) 30 seconds of idle time.
I'm going to talk with upstream about clarifying the tickbox label, but otherwise I don't think this feature will be coming back as it was. [1] https://live.gnome.org/Design/SystemSettings/Screen -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-settings-daemon in Ubuntu. https://bugs.launchpad.net/bugs/884041 Title: Screen brightness not adjusted when switching from AC to battery Status in Ubuntu on the Nexus 7: Confirmed Status in “gnome-settings-daemon” package in Ubuntu: Confirmed Bug description: I upgraded my Samsung NC 10 to Oneiric recently. Since then, switching between AC and battery power has no effect to screen brightness. Adjusting the brightness manually works but is quite annoying. I added the regression tag since this didn't happen in Natty and older. ProblemType: Bug DistroRelease: Ubuntu 11.10 Package: gnome-settings-daemon 3.2.0-0ubuntu5 ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4 Uname: Linux 3.0.0-12-generic i686 ApportVersion: 1.23-0ubuntu3 Architecture: i386 Date: Mon Oct 31 01:00:12 2011 EcryptfsInUse: Yes InstallationMedia: Ubuntu-Netbook-Remix 9.10 "Karmic Koala" - Release i386 (20091028.4) SourcePackage: gnome-settings-daemon UpgradeStatus: Upgraded to oneiric on 2011-10-01 (29 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-nexus7/+bug/884041/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
