IBM T60 and Lenovo T60, dimmed screen when on battery?

[TP_]

Hi,

I tried searching, but I couldn't find anything helpful.

I have a IBM T60 14" with XP and a Lenovo T60 with the 15" IPS and Linux Mint installed.
Both dim their backlightning significantly when the AC adapter is unplugged.
Using FN + brightness keys, function as they should, I can lower and raise the brightness, but I can't raise the brightness to the level when AC adapter is plugged.

Since its related, my T43 also does this.

Any ideas?

Regards
//Mattias

[TPFanatic]

this is intended. there may be a option in Bios Setup to disable the screen dimming.

[dr_st]

this is intended. there may be a option in Bios Setup to disable the screen dimming.

Yes, there is. It's called set Screen Brightness to High.

[TP_]

How can I have missed this?

Many thanks, this was it.