Thread: 2 folders in Sys/Class/Backlight?

issue: backlight brightness not change.

more detail: brightness not change, using both 'system settings->screen', or fn keys (brightness bar shows , moves, screen brightness not change).

notcied post in thread (http://ubuntuforums.org/showthread.php?t=1866283) having multiple folders in sys->class->backlight...

i have 2 folders too!

'intel_backlight' , 'acpi_video0'

using function keys, alters value in acpi_video0's 'brightness' file - doesn't alter brightness of screen.

if add 'backlight=vendor' in grub, function keys edit value in 'intel_backlight brightness file. - again doesnt change brightness of screen.

computer: fujitsu siemans pi2515, intel integrated graphics, no hdd partition.


already tried:

-editing grub contain: acpi_osi=linux acpi_backlight=vendor

-http://ubuntuguide.net/change-screen-brightness-with-fn-key-in-ubuntu-11-0410-10

-sudo apt-get install acpi

-$ sudo setpci -s 00:02.0 f4.b=20

-brightness not adjust in fallback mode either.

-reinstalling os, using linux mint (same problem).

-upgrading , downgrading bios.

many reading, understand problem may need bit of linux pro sort. if anyones challenge i'll spend amount of time being walked through this, posting results. don't want give here!

unsure of rules, apologies if bumps not allowed. still got problem, @ great, or words of advice. many thanks. zebrapie.

Forum The Ubuntu Forum Community Ubuntu Official Flavours Support Hardware [ubuntu] 2 folders in Sys/Class/Backlight?

Ubuntu