7740 display brightness

Hi

When I boot the PC, the BIOS password screen is sometimes really dim, but sometimes really bright. Is there an ambient light sensor somewhere that's affecting this?

Also (not sure if this is related to the above) on battery power (not on mains power) the screen brightness fluctuates a lot. Is there a way to stop this?

Many thanks

 

Intel Graphics control panel.
"Power" section.
Disable the "display power saving technology" on battery feature.

 

Brilliant, thanks a lot.

Does this affect the BIOS password screen brightness too, or only after windows has booted?

 

This is only after Windows has booted, but I don't think that the "feature" should be active in the pre-boot BIOS screens, since it is controlled by the Windows Intel GPU driver ...?

 

That's what I was thinking, but I wonder why the BIOS screen is sometimes really dim? What could be controlling that?

 

There are settings to control the screen brightness (on and off battery) in the BIOS setup. However I think that it just "remembers" the last state that the screen was in, so if you change the brightness settings from within Windows they will be retained in the BIOS. I'm not totally sure about this, I don't mess with it much (I just leave the brightness at max all of the time, I'm not away from an outlet for extended periods of time).

 

I almost never work just on battery either, so also want max brightness all the time.

Seems your suggestion has fixed the windows brightness, and I've also (on your suggestion) gone into the BIOS brightness setting - it was on 100% for battery, and 50% for mains power (hence the dim BIOS screen most of the time - I obviously hadn't clocked that it was only when it was on battery it was bright). So both things are now fixed thanks to you - much appreciated!!