I have an ASUS N56V where the Fn-F{5,6} keys do not work natively (no output in xev when pressed). This is very easily worked-around using acpi_os="!Windows 2012". The resulting control is something along the 3-10 range (10 being brightest and 0 being off, these are not the actual numerical values), which means I can't dim my backlight beyond a certain value. Similarly, using xbacklight and setting to 0 actually gives a "3" backlight, not totally blank. Setting /sys/class/backlight/intel_backlight/brightness to 0 does turn the screen off though. The problem is that if I write a simple script to adjust brightness and bind that using xbindkeys, the native handler still works for a fraction of a second before the value I calculate takes effect. This results in a brief flicker everytime I press the keys. Conclusion - I want to disable this native handling of Fn-F{5,6}, is this possible or is this not software-controlled?