...as additional information, I booted with a live media (Ubuntu 13.10 x64 Gnome edition) and I have connected an external monitor (screen mirroring).
The interesting thing is that if I press fn f4/f5 keys, the hud indicator (that is also displayed on the external monitor) shows me brightness icon and the bar going left and right but nothing happens on the laptop screen.
Also I tried with:
cat /sys/class/backlight/intel_backlight/actual_brightness
that initially gives me 4845 and then values change while pressing the fn keys and repeating the above command.
So it seems that device is recognized by the system but changes have no effect on the physical device.
Also echo 1000 > /sys/class/backlight/intel_backlight/brightness has no effect.
...as additional information, I booted with a live media (Ubuntu 13.10 x64 Gnome edition) and I have connected an external monitor (screen mirroring). backlight/ intel_backlight /actual_ brightness
The interesting thing is that if I press fn f4/f5 keys, the hud indicator (that is also displayed on the external monitor) shows me brightness icon and the bar going left and right but nothing happens on the laptop screen.
Also I tried with:
cat /sys/class/
that initially gives me 4845 and then values change while pressing the fn keys and repeating the above command.
So it seems that device is recognized by the system but changes have no effect on the physical device.
Also echo 1000 > /sys/class/ backlight/ intel_backlight /brightness has no effect.