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I can set the brightness of my laptop screen already via /proc. I can read and change the value.

Now I've set the value to 33 and then I went into gnome power management and enabled the option that it should reduce the backlight brightness being on battery.

That works, the screen gets darker.

If I now read out the current setting from /proc it still says it's 33. So I assume that there is another node in /proc to be used to control the brightness.

The node I use so far is:


I'm using the nouveau driver. With the nvida driver the brightness can not be controlled.

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up vote 0 down vote accepted

With the nvidia driver, the brightness can be controlled the same way, if the according option is activated.

This is done under the Device setting in xorg.conf:

Option "RegistryDwords" "EnableBrightnessControl=1"


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