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Acer Aspire 4349 backlight unable to dim, slider moves only with no effect, NON-BIOS controlled, how-to configure software to actually dim the sucker rather than just moving a slider-indicator?

Tried suggestion found by using Cairo Dock and "Luminosity", but it's not the real deal, (not looking for a mere gamma adjustment), although this "gama adjustment" works (looks like shyt, though), I'm looking for an actual effective LED back-light controller.

I think I made a mistake buying an Acer, sticking with MSI, for rats sake, at least, their backlight is controlled directly through the BIOS! What kind of crap controls this backlight with "software"...hell, just 2 LED indicators that work "weirdly", only thing I like 'bout this acer is surprisingly the Celeron B815. Not a damned thing else!

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Try this:… Regards, – Celso Sep 6 '12 at 10:44
sudo sed -i.backup -r '/^GRUB_CMDLINE_LINUX_DEFAULT=/ s/=.*/="quiet splash pcie_aspm=force acpi_backlight=vendor"/g'  /etc/default/grub
sudo grub-update

Note that we have made a backup in the sed command, which ensures a recovery on error

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