[LENOVO 0768BXG] Brightness does not increase properly

[Neil Wilson]

Binary package hint: gnome-power-manager

Jaunty Beta.

The laptop system is receiving input from the Brightness controls on this laptop (Fn + F10 and Fn + F11), but the power manager moves the brightness slider up and down fairly randomly and the screen merely flickers. This is with AC power connected and disconnected.

If I kill the power manager then the brightness controls work correctly (although I don't get a sexy translucent graphic on screen :)

Description: Ubuntu jaunty (development branch)
Release: 9.04

Description: Ubuntu jaunty (development branch)
Release: 9.04

[Neil Wilson (neil-aldur)]

gnome-power-manager:
  Installed: 2.24.2-2ubuntu7
  Candidate: 2.24.2-2ubuntu7
  Version table:
 *** 2.24.2-2ubuntu7 0
        500 http://gb.archive.ubuntu.com jaunty/main Packages
        100 /var/lib/dpkg/status

[Neil Wilson (neil-aldur)]

The 'Brightness down' key seems to send the brightness to minimum in a couple of presses - and then of course I can't go back up again.

[Neil Wilson (neil-aldur)]

Same issue with the latest updates.

gnome-power-manager:
  Installed: 2.24.2-2ubuntu8
  Candidate: 2.24.2-2ubuntu8
  Version table:
 *** 2.24.2-2ubuntu8 0
        500 http://gb.archive.ubuntu.com jaunty/main Packages
        100 /var/lib/dpkg/status

[Nadezhda Gesheva (daebaa)]

Same problem with Lenovo SL 500.
After restart the brightness is 85 and if I change it , can`t bring it back.

[Anton Maier (anton-maier)]

Same problem with lenovo SL 500
you can change the brightness by using the slider of the brightnessapplet...

[Anton Maier (anton-maier)]

i mean 3000 n100

[Scott Howard (showard314)]

Thank you for your report and helping making Ubuntu better.

Can you check out is bug #376924, specifically a link to a potential patch at: http://marc.info/?l=linux-acpi&m=124456088526538&w=2. If you are able, try that patch in acpi and report if it helps.

[Neil Wilson (neil-aldur)]

Yup, I'd say that's the same bug. On the Lenovo you get

levels: 0 14 28 43 57 71 86 100
current: 43

And the brightness leaps between the bottom four values on that list.

Marking as duplicate