Hello,on my laptop Acer (model 4750) I have to pass kernel parameter acpi=off to be able to setup screen brightness via the Fn key.
However the screen resolution is then downgrade (to 1024/640 from 1366/768). Why ? Which solution should I try ? Note: I'm using latest Squeeze 22.214.171.124.I tried same thing with Ubuntu 11.04 : it works perfectly as FN keys works without any loss of screen resolution.