Laptop LCD Brightness steadily decreases with power status change

[Andy Walker]

Release: Ubuntu hardy(development branch) 8.04

System: System76 Darter Ultra "DarU2" (msi manufactured)
Graphics: Intel GMA X3100
CPU: Core 2 Duo T7700 2.4 GHz 800 MHz FSB 4 MB L2

Symptoms: Brightness levels steadily decrease as power is plugged in and removed.

To reproduce:
1) Remove power, <battery brightness> level will appear.
2) Plug power back in, brightness will revert to <AC brightness> minus 1 or 2 levels.
3) Remove power again. Brightness will decrease to <battery brightness> minus 1 or 2 levels.
4...) repeat 2-3

Repeating this cycle will steadily lower BOTH levels of brightness until <battery brightness> is the minimum level and <AC brightness> is one or two levels above minimum.

[Andy Walker (walkeraj)]

Looks like this functionality is even more broken than I thought. Upon disabling and re-enabling "reduce backlight brightness" in the "On Battery Power" tab of Power Management Preferences, I'm receiving a whole host of funny effects when I try and change my brightness manually with the fn keys. It looks as if the power management subsystem is bogged down or running extremely slowly. Changes to the brightness are not immediately applied and the brightness will sometimes change long after I've pressed any keys. Further, the applet displays an empty battery icon saying that it could not read the status of the battery for long stretches of time. Eventually, it will show the proper status, but only one or two minutes after the power state has changed, and even then it is not reliable. Currently, my laptop reads that it is plugged in when it is not, and it is set to minimum brightness.

[Vojtěch Látal (vojtik)]

Isn't this bug a duplicate of https://bugs.launchpad.net/ubuntu/+source/gnome-power-manager/+bug/203108 ?

[Andy Walker (walkeraj)]

Good eyes. Looks like it is. My bug report, however, I think is a
much better description of the problem and (with the comment) its
associated side-effects. Should I mark my bug as a duplicate anyway?

On Tue, Mar 25, 2008 at 3:26 AM, Vojtěch Látal <email address hidden> wrote:
> Isn't this bug a duplicate of https://bugs.launchpad.net/ubuntu/+source
> /gnome-power-manager/+bug/203108 ?
>
> --
> Laptop LCD Brightness steadily decreases with power status change
> https://bugs.launchpad.net/bugs/206228
> You received this bug notification because you are a direct subscriber
> of the bug.
>
> Status in Source Package "power-manager" in Ubuntu: New
>
> Bug description:
> Release: Ubuntu hardy(development branch) 8.04
>
> System: System76 Darter Ultra "DarU2" (msi manufactured)
> Graphics: Intel GMA X3100
> CPU: Core 2 Duo T7700 2.4 GHz 800 MHz FSB 4 MB L2
>
> Symptoms: Brightness levels steadily decrease as power is plugged in and removed.
>
> To reproduce:
> 1) Remove power, <battery brightness> level will appear.
> 2) Plug power back in, brightness will revert to <AC brightness> minus 1 or 2 levels.
> 3) Remove power again. Brightness will decrease to <battery brightness> minus 1 or 2 levels.
> 4...) repeat 2-3
>
> Repeating this cycle will steadily lower BOTH levels of brightness until <battery brightness> is the minimum level and <AC brightness> is one or two levels above minimum.
>

[Vojtěch Látal (vojtik)]

Andy, it's up to you. But I think one of them should be marked as a duplicate of the other one. I'm just having same problem and I've seen two similar bugreports. I've tried to find out which bug should be marked as duplicate (whether newer one or the one worse described), and I've found: https://wiki.ubuntu.com/Bugs/HowToTriage#head-170e00a7154fcfc87f0fc50f65bba9cff7ab27fe where it is said: If they (similar bugreports) describe the same root cause, decide which report should be the primary one. This should be the one that's the most understandable and contains the most information.

I'm not sure which one. So, please decide:-)