Screen brightness locked


New Member
Dec 24, 2015
I have a Lenove Ideapad z400 that came with Windows 8. Ever since I “upgraded” from Windows 8.1 to 10, the brightness adjust buttons immediately make the screen change to the lowest brightness setting – unusable in all but near-darkness.

- The first time it happened, I updated the graphics driver (Intel HD 4000), and that fixed it.

- The second time it happened, I had to fully unistall the graphics driver and delete the software. Switching to generic PnP monitor restored the brightness, and the brightness stayed up when I re-installed the graphics driver.

- The third time it happened, I had to fully uninstall the graphics driver, delete the software, and uninstall the default driver. When I restarted the computer, the automatic installation of the default driver brought the brightness back up.

- Recently my HDD died, and I had to re-install Windows 8. Assuming this fixed the whole problem, I stupidly tried to use the brightness adjust button again. It’s now locked on the lowest setting, and nothing is working to fix it.

o Obviously, I’ve tried the usual suspects – power settings, automatic brightness control, changing brightness from the settings menu rather than the buttons. Nothing. The control says that the brightness is all the way up, but the screen is as dim as the lowest setting and moving the slider changes nothing.

o I updated the graphics driver.

o I uninstalled the graphics driver. Restarting automatically reinstalled it.

o I uninstalled the graphics driver and checked “delete software.” Restarting automatically reinstalled it again. (and again and again. What on earth??)

o I manually deleted each driver file. It’s not re-installing now, but the brightness is still low.

o I disabled/re-enabled and uninstalled/reinstalled the default driver.

o I checked BIOS for any setting related to screen brightness.

o I reset BIOS to default settings.

o I’ve searched the internet for any information related to this problem.

o The only thing I can think of is to wipe the HDD and start over again. Having done so recently, it wouldn’t be that big a deal to do again – but it’s still a pain, I’ll have to endure about 4 hours of Windows updates, and I’m not sure it’ll fix the problem.

o Or I can throw this PC out and get a Mac. Being completely fed up with the constant updates and the resulting instability of Windows, I may do this anyway. But I’d like to get this computer working again, at least for a backup.

Two other things that might be significant: 1. It doesn’t start bright then go dim, as if BIOS starts it bright then something else dims it. It’s just dim from the very first. 2. I can connect a second monitor, and the second monitor works fine. (This is using the graphics driver, of course – generic PnP monitor won’t support a second monitor.)

Any advice? Or is this thing a paperweight?

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Update: I created a restore drive from the computer then reset back to the initial backup; I also reset using a restore usb from another Windows 8 laptop. Neither fixed the issue.


I have kind of the same issue, help :(

I know this is a bit old, but this affects my laptop as well so I image its a Windows 10 bug. However if you keep pressing your brightness up key even when it shows it's maxed it should get brighter but only when it shows its maxed out.

*EDIT* I guess I was never really concerned with this be I don't turn my brightness up anyways, but it dawned on me what the issue is. See if this fixes it for you.
  • Go into Control Panel > Power Options
  • Click Change plan settings next to your power plan > Change Advanced Power Options
  • Go to the Display section and look for "Enable Adaptive Brightness"
  • Turn that off and test your brightness

It uses a light sensor to sample light from your environment and dim accordingly

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