Ubuntu MATE 16.04 laptop brightness not preserved

1.When on battery screen brightness drop to 50%, whick is okay .
2. After that I increase brightness with function keys to say 80%, which works ok.
3. After the screen dims, it returns back to 50% again but not 80% ie: the value set by the function keys.
How can this be fixed or is it related to MATE Desktop. Other desktops like unity, xfce, cinnamon works as expected.
This is the output of lspci | grep VGA

 ~ $ lspci | grep VGA
    00:02.0 VGA compatible controller: Intel Corporation Mobile
    945GM/GMS, 943/940GML Express Integrated Graphics Controller (rev    03)

I have the same issue. I checked the settings in TLP. No joy…

HI chaps,

have you checked this out?:


cpufredq is installed by default but for most users it should probably be removed as it can interfere with other power saving and CPU frequency management tools. To remove cpufreqd open a shell with CTRL + ALT + t and do the following:

sudo apt-get update && sudo apt-get dist-upgrade && sudo apt-get purge cpufreqd

Info taken from here :thumbsup:

If I disable “reduce backlight brightness” on battery and set brightness with the command gsettings set org.mate.power-manager brightness-ac 70
then after dimming it returns to the value I set. So I think it reads the brightness ac value when to restore brightness after dimming. So function keys aren’t writing the brightness value at all.


same problem here with this video card. Cpufreqd wasn’t installed. The installation of it didn’t help either with Mate. Are there any new insights about this topic?

Thanks in advance.


I think this is a mate power manager bug.

Checked out Linux Mint 18. It comes with Mate 1.14. Same behaviour there too. This is critical on a laptop operating on a battery. And there is no help at all. Better off with something else.

We should be reporting this to the mate-power-manager github and making sure they are aware. The mate core tools are not supported here from my understanding. This is just integrating mate with ubuntu.

I am on the MATE core team. I do make notes when I see stuff like this. I need to retest this, because I tested this exact issue on my laptop a couple of months ago and it worked fine.

@wimpy Thanks, I was doing some testing with some of my friends and they have an older version of my laptop (XPS 13) and their laptop seems to work fine. Mine on the other hand seems to struggle with the power manager and how it adjusts the brightness on the screen and keyboard in Mate.

On the Github for mate-power-manager it seems that some of the people are having similarix issues with new computers.

Current open issues:

Old Fixes that people tried:

It is even worse. I am a newbie at Linux and just got Ubuntu Mate installed for 2 days now. I have the problem that my screen is constant blowing at full power. In the daytime it is doable but iat knight it burns my eyes out. I can not change the brightness of the light. I have installed the Nvidia drivers for my Asus Rog G751JY. Also some keyboard problems at that. I guess i am doing a couple of things wrong as a newbie but if someone knows a solution i would appreciate that.

A quick solution is to add the brightness applet to the top panel and then pull the slider down!.

Right click top panel > Add to Panel > Brightness Applet > Add:

Hi Wolfman, Thanks for the reply. I have this slider on the desktop. It makes no difference when changing the slider. Not even after a reboot.

Hi @Tuihanti,

did you not put it on the panel?. :confused:

Hi Wolfman, yes i did put it on the panel.

I also remember that it was working ok before maybe mate 1.12. something. But it is broken now. Changing brightness with function keys was changing the brightness on ac slider value before. I have also reported a bug on github.

6 posts were split to a new topic: Laptop screen brightness

I am using the proprietary graphic drivers now and i am able to change the luminescence now. Not the way i want but it works. Still need to figure out how to color calibrate the monitor.
Let’s hope these problems can be solved.

This version works as expected, mate-power-manager_1.12.0.1-1+rosa_amd64, which I downloaded from mint repository for linux mint rosa. But versions after that does not work, nor 1.12.1, neither 1.14 or 1.16.
Thanks in advance.
I am using xfce-power-manager as a work around.

Hi all. I tried to use Ubuntu 16.10 with Mate 1.16. I seem to have very bad screen brightness problems on a Thinkpad with Intel HD 520. The brightness jumps all over the place and in general it is way too bright and literally hurts my eyes. Was so disappointed because I really wanted to switch over to Mate. Not sure if this is the same as the above problem but essentially I had no option but go back to Gnome. Didn’t have this problem on Gnome, KDE or Cinnamon