Screen Brightness Cannot be Changed when M1330 is Unplugged

Before anything else.. yes of course I know how to change the brightness of the screen and I've tried it!

I've only had my M1330 for a month or so. The first few weeks there were no problems, and there still is none when attached to the power source. However when I unplug it, the screen brightness goes down to what appears to be the dullest setting, even though I've put it on max.

I've been all through the power options but nothing seems to work. It says it's on the highest "On Battery" display brightness - then I unplug it and the screen goes dull. The Fn + arrow keys work properly when plugged in, however when not, there only seems to be two very faintly different settings (both of which are useless).

This is very annoying! Can hardly use it at all on that brightness setting. Thank you so much to anyone who can help me out! =)

 

Increase the brightness in BIOS

 

Thank you Zeusmd! Yes I had a look around the BIOS and found under VIDEO > BRIGHTNESS that the display was stuck on the factory default 3/8 for "on battery" power. I turned that up to 8 and now everything's functional again. I can turn the brightness back down when it on the battery too, it all just works as it should.

What a simple solution.