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I'm new to this forum and thought I'd try it out. So, much like every edition since about 11.10 brightness control doesn't work "out-of-the-box". I have a Toshiba Satellite T110-12P and although I've managed to solve the problem in earlier editions, this time I cannot. I have tried adding the "acpi_backlight=vendor" kernel parameter but unlike other times, it did not solve the problem. I found a somewhat complicated solution by running some commands but I'd like to find a more comfortable one. Do you have any suggestions?

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Could you share the commands you used? – Argusvision Apr 26 '13 at 21:21
Sure, I used: "lspci | grep -i vga" to check for the BusID and "sudo setpci -s 00:02.0 F4.B=90" to adjust the brightness. Replacing "90" with my desired brightness level. – Duarte Cecílio Apr 26 '13 at 22:41

I have a solution that worked on my Acer Aspire V3-531G laptop with Ubuntu 13.04-64 bit. This solution does not depend on the hardware, hence I dare to recommend it to you:

  1. As root, open the /etc/default/grub file in your favourite text editor.

  2. Change the line GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" to GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux"

  3. Save the file

  4. As root, run update-grub

  5. Reboot

  6. Enjoy! :-)


Hope, this helps!

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Already tried it, and all variantes of kernel boot options. None worked, unfortunately... – Duarte Cecílio Jul 30 '13 at 1:03

I have the same thing on one of my Toshiba-Satellite Laptops (the other one works fine). Brightness is always set to minimum after reboot. I couldn't find a real solution, so I installed a little brightness-indicator, which shows a button in the panel. After startup I can change brightness without the need to open system settings.

"Installing the applet in Ubuntu 11.10 through 13.04 is as easy as running the following commands in a Terminal:

sudo add-apt-repository ppa:indicator-brightness/ppa

sudo apt-get update && sudo apt-get install indicator-brightness

If a PPA is a bit too much for you, you can grab a .Deb installer from the project launchpad page"

You can find the details of the indicator at:

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Welcome to Ask Ubuntu! Whilst this may theoretically answer the question, it would be preferable to include the essential parts of the answer here, and provide the link for reference. – saji89 Jul 23 '13 at 4:43
Thanks, added essential parts. – kleinempfaenger Jul 23 '13 at 13:05
The thing is, I already tried installing said brightness indicator but it didn't work, the reason being that I can't ajust brightness through system settings. I change the setting but the brightness stays the same... – Duarte Cecílio Jul 24 '13 at 14:41

protected by Community Aug 28 '13 at 15:58

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