Comment 5 for bug 562005

I can now force the nvidia driver to control the backlight. I don't know why it didn't work before, I did 2 hard reboots and the setting didn't take effect. Regardless, the nvidia's backlight controller is still less effective than the one used by nouveau or in a text mode VT. The nvidia driver's backlight control should not be force-enabled by default because it changes the brightness in inconsistent increments and causes a buzzing noise to emanate from the LED backlight. This noise is at different frequencies according the the level of brightness, and sometimes ceases for a fraction of a second while the backlight is changing from one brightness level to another. Is there anything I can do to give a comparison of the brightness levels passed by nouveau driver or in a text mode VT? I'd assume there is something in Sysfs.

What is the difference between how a text mode VT or nouveau change the backlight brightness, compared with how nvidia does it? Gnome should be forced to use a non-nvidia method by default.