I'm trying to get some control over the brightness of my Samsung QX411 (Integrated Intel graphics) on Ubuntu 3.04 (though I have the exact same issue on 12.04 and on Mint)
Using FN+up/down lowers the screen brightness from max to one peg down or back up. If I try to bring the brightness down any more, it flickers but stays the same.
I have full control of the brightness in Settings, but that's delicate and gets reverted to full max if I open up the brightness settings again, use fn+up/down, the screen goes into power saving, or after log out.
The closest I got was adding
to a line in /etc/default/grub, [source]
I could consequently lower the brightness a couple of pegs down to the minimum with FN+down, but then it's as if the problem got inversed, and I'd get stuck in the bottom tier, I could only increase the brightness by one peg and back down. Rebooting would revert to max brightness.
acpi_osi=, acpi_osi=Linux, acpi_osi=vendor, acpi_osi='!Windows 2012', acpi_backlight=Linux, acpi_backlight='!Windows 2012'
instead didn't do anything for me.
I've also tried adding
echo 2000 > /sys/class/backlight/intel_backlight/brightness to /etc/rc.local,
where my max value from
cat /sys/class/backlight/intel_backlight/brightness is 4648, which didn't do anything. (same result with echo 2000 > /sys/class/backlight/acpi_video0/brightness) source
Samsung tools also didn't help in this regard.
I've spent days on this, it's getting quite frustrating. Any help would be greatly appreciated.