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I have problem with my new netbook. I installed Ubuntu 12.10 and I can't use my brightness key's (Fn+F5/F6). When i use them OSD appears and indicates the increase or decrease of brightness but nothing really happens to screen. I used this command from terminal(and it worked):

sudo setpci -s 00:02.0 F4.B=xx

But I want use my Fn keys. Is it possible to do this?

Thanks for help!

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Possible duplicate: askubuntu.com/questions/221826 –  user98085 Dec 19 '12 at 12:32

1 Answer 1

up vote 4 down vote accepted

Copy-Paste from here the commands below (to your terminal) , with order and one at time


sudo sed 's/GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"/GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi="/' -i /etc/default/grub


sudo update-grub

Reboot your system and see if Fn (for brightness) works.

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Also fixed my problem for ASUS S551LB. –  shantanu Apr 18 at 7:19
Fixes the brightness buttons for ASUS G56jr too! Thank you! –  Dr. Nefario Aug 2 at 9:26
Worked for Asus Zenbook. Thanks! –  umpirsky Sep 14 at 8:57

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