I tried using Fn+<- to turn the brightness down, and it showed the little sun icon indicating the brightness was turning down, but it didn't do anything.
I also tried xbacklight -set 100 but that didn't do anything either.
I recently installed Ubuntu 9.04 (x64) on my gateway m-series laptop. Works great minus the fact that I can adjust the screen brightness. when using an applet or my keyboard, ubuntu shows that it is being adjusted, but the actually screen brightness is constant(100%). Besides the fact that it is killing my battery, my eyes dont really adjust well to it.
I have a gateway m-series laptop, and I just recently installed ubuntu 9.04 (x64) in attempts to broadening my OS use. For the most part this is working great, but my current issue is with my screen brightness. When attempting to adjust the brightness either through ubuntu or on my keyboard(fn+up or down) ubuntu shows that I am adjusting the brightness but there is no actual change.