It seems to me that my Function keys (Fn+F9/F10) work fine and pressing them changes the brightness value correctly, but I feel that this value isn't read in GNOME by some other module that operates a backlight lamp or something like this. Outside the GNOME it all works fine. I don't know if it is a GNOME issue or X server issue or what else it can be
BTW, when I exit to console using Ctrl+Alt+F1 and then execute
"echo -n 1 > /sys/class/ backlight/ acpi_video0/ brightness" video/C14B/ C15F/brightness "
or
"echo -n 30 > /proc/acpi/
all works fine.
It seems to me that my Function keys (Fn+F9/F10) work fine and pressing them changes the brightness value correctly, but I feel that this value isn't read in GNOME by some other module that operates a backlight lamp or something like this. Outside the GNOME it all works fine. I don't know if it is a GNOME issue or X server issue or what else it can be