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I installed Ubuntu and KDE too on my MacBook Air 4,2, but I realised I cannot change brightness in KDE. In Unity, it works without problem. Other keyboard keys works properly, sound, play, etc., but I cannot change brightness in KDE. I tried KDE4.8.4 and KDE4.9 beta. Thx

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1 Answer 1

I have laptop brightness buttons working. If I wouldn't I'd play with


files (do You have them - or some similar files there?). See what is written there - some shell commands.

Also in the old days bright could have been controlled with:

echo -n 100 > /proc/acpi/video/VGA/LCD/brightness # sets br to 100%

but now the mechanism is changed.

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