Ubuntu
gnome-shell package

  1. Bug #1520355
  2. Comment #20

Comment 20 for bug 1520355

Revision history for this message
benbennett (benbennett) wrote :

Enabling dual graphics/nvidia optimus in bios fixed the problem for me.
When dual graphics is disabled the driver load produces the following path.
/sys/class/backlight/acpi_video0/

but with dual graphics enabled , the following path is created.
 /sys/class/backlight/intel_backlight

Finally I am pretty sure unity/xbacklight are using xrandr to change the brightness so that ends
up using the graphics card driver to change the brightness.

Where gnome is using the kernel path for an acpi call.

I don't if it kernel bug or bios or video card bug for not handling the acpi call correctly.

Might be better if gnome used xrandr instead or be able to switch.