1. Home
  2. Windows Tips
  3. Why does my screen keep dimming

Why Does My Screen Keep Dimming? (Windows 10 and newer)

If your iPhone or other mobile device keeps dimming, it’s likely due to an auto-brightness feature that is often turned on by default. This feature senses the light in the room and adjusts your brightness to compensate. Dark room? Dim screen. Bright room? Bright screen. You can easily turn this off in the same area that lets you adjust the brightness of your device (usually by tapping a button next to the brightness bar). 

Windows 10 and newer include a similar screen brightness feature. If you’re wonder “Why does my screen keep dimming?” then keep reading for several solutions you can employ, like editing Device Manager and other settings.

How to Fix Windows 11 & 10 Screen Dimming

In this article though, we’ll go over screen dimming issues that occur on Windows 10 and newer computers. All screens have a backlight which determines how bright or dim they are. The brightness of a screen will span a certain level ranging from very dim to exceptionally bright. Depending on how you have your work station set up, and how much light is in the room, a user is free to choose how bright the screen is, and to change it whenever they need to.

Brightness can be changed from a keyboard, buttons on a monitor, and from settings provided by the operating system that is installed on a system. All three will change the same setting and are essentially different ways to doing it. Regardless of how you change the brightness of the screen, it will remain set at a level until you choose to change it again.

Laptop screen keeps dimming or brightening

  1. Why Does My Screen Keep Dimming?

    If your laptop’s screen keeps dimming or brightening, it may point to a software problem or a hardware problem. Hardware problems are likely going to require that you take the laptop in for repairs but software problems can be solved through various app settings, all described below.


    Windows 10 Screen Dimming (SOLUTIONS)

    Windows 11 & 10 Screen Dimming (SOLUTIONS)

    1. Turn off adaptive brightness

    Laptops often come with sensors that will check the ambient light in a room. If the light from the surrounding environment changes, or the sensors thinks it has changed, it will adjust the brightness of the screen to suit the level of light. This feature is called adaptive brightness, and it may be responsible for the screen dimming or brightening.

  • Open Control Panel. The quickest way is to search for it from the Start menu.
  • Go to Hardware and Sound.
  • Select Power Options.
  • Choose Change plan settings next to your current power plan.
  • Select Change Advanced Settings.

The power plan settings in Control Panel

  • Expand the Display settings.
  • Expand Enable adaptive brightness under it.
  • Turn it off for both battery and plugged in states.
  • Press OK.
  • Repeat this for all power plans you use.

win10-adaptive-brightness-1

2. Disable Night Light

Night light is a feature in Windows 11 that will automatically adjust the screen brightness of your computer to show warmer colors. The idea is to help you sleep or correct vision problems that might occur from a bright screen. This feature is typically manually enabled, but depending on your setup, you might even have the scheduled night shift enabled, meaning the screen dimming automatically adjusts at certain times of the day. You can disable this easily through the Settings app.

  1. Open Settings via Win+i.
  2. Select System and then Display Night light from the right pane.
  3. Select Turn off now at the top of Settings to instantly fix the screen brightness issue.
  4. If the Schedule night light toggle is on, switch it off. 

 

Windows 11's Night light settings

Tip: Some users report that automatically dimming the screen with night light improves battery health on their laptop. However, its wise to turn this feature off if the screen dims when you don’t want it to, like when you need to see the real display color (e.g., when using photo editing tools).

3. Update graphics drivers

While uncommon, outdated graphics drivers can cause the screen to dim or brighten. Updating drivers to the latest version should fix the problem. You can do this through the display adapters area of Device Manager.

  • Open Device Manager.
  • Expand Display adapters by pressing the arow next to the category heading.
  • Right-click the on-board graphics card and select Update driver.

display-drivers-win-10

  • Select Search automatically for drivers.

 

Driver update options in Windows 11

<file:update-drivers-device-manager-windows-11; alt:>

4. Calibrate the color of the display

Windows 10 and newer include a tool that can improve the color of your display to make sure you see colors as they really are.

  • Search Windows for calibration, and then open Calibrate display color when you see it in the search results.
  • Move the window onto the display you want to calibrate.
  • Select Next on the welcome screen.

Display Color Calibration tool in Windows 11

  • Follow the on-screen steps by pressing Next after you read each step. You’ll be told how to use your monitor’s menu buttons to adjust screen brightness and contrast, color balance, and more.

5. Run Power troubleshooter

Windows 10 has a troubleshooter for power-related problems (e.g., a system component is unable to draw as much power as it needs in order to function). Windows 11 includes some troubleshooters, too, but it does not have one for power-related problems.

  1. Open Control Panel.
  2. Use the drop-down menu at the top right to change the view to Small icons.
  3. Select Troubleshooting.
  4. In the column on the left, select View All.
  5. In the list, select Power.
  6. Run the Power troubleshooter and apply all fixes it recommends.
  7. Restart the computer.

Run-Power-troubleshooter

6. Examine power sockets, ports, and wires

If your system isn’t getting a steady current, it may be triggering a change in the power plan. Power plans can change based on the source of power (battery or DC). Run through the following fixes to see if any of them can address the screen dim problem.

  • Make sure the laptop is securely plugged in.
  • Make sure the current isn’t fluctuating. If it is, using a current stabilizer will help.
  • Make sure the socket the laptop is connected to isn’t damaged.
  • If you’re using an extension board, make sure its wire isn’t damaged.
  • If you’re using an extension board, make sure it isn’t overloaded and that nothing connected to it is causing electric surges.
  • Remove any power-hungry items that may be connected to the same board/socket.

7. Change screen resolution

It’s possible that you’ve set a screen resolution that isn’t the best for your display. The screen dimming and brightening may be a result of various apps or the OS trying to work with the screen resolution that’s been set.

  1. Open the Settings app (Win+i keyboard shortcut).
  2. Go to System > Display.
  3. Open the Display resolution dropdown.
  4. Select the resolution that has ‘Recommended’ written next to it.
  5. Restart your PC for good measure.

screen-resolution-win-10

8. Edit Windows Registry

If the above steps haven’t worked out to disable auto brightness, there is another potential software solution before we move onto the hardware step coming up next. This involves editing the Windows Registry (a critical part of the Windows OS), so be careful to stick to these steps and nothing more.

  • First, open Command Prompt and enter this command:
    powercfg /L
  • Copy the GUID next to the power plan you want to edit, and paste it somewhere like Notepad. The one with the asterisk is probably the one you want to copy.

Command Prompt results for powercfg command

  • Open Registry Editor. One quick way is to search Windows for regedit, and then select the utility from the search results.
  • Copy the following path, and then use it to jump to that location in Registry Editor:
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Power\User\PowerSchemes
  • Using the GUID you recorded earlier, open the registry key/folder that corresponds to that value. In our example, it’s 381b4222-f694-41f0-9685-ff5bb260df2e.

Windows 11 Registry Editor path

  • Within that key, open this subkey:
    7516b95f-f776-4464-8c53-06167f40cc99
  • Continue one more time to open the next subkey. You should now see a value in the right pane called ACSettingsIndex. Double-click it.
  • Change the Decimal value to any number between 0 and 100 to specify the screen brightness for when your laptop is plugged in.

ACSettingsIndex value in Windows 11 registry

  • Select OK to save. Reboot your computer to apply the changes.

9. Examine potential hardware problems

Hardware problems may be causing the screen to dim or brighten and that means you have to take the laptop in to be fixed. Your laptop’s battery, power supply unit, or graphics card may either have come loose or they may have been damaged. Opening it up is the only way to check. If something has come loose, the repair shouldn’t take too long or cost too much. If a hardware component has been damaged, you will have to replace it.

Laptop Screen Brightness Changes On Its Own? CONCLUSION

Problems with a display usually happen when a graphics-heavy app like a game is being run.

If you game often, and you’re not careful about your system heating up, it is possible that a hardware component is damaged and is causing these screen brightness issues.

If not, it may simply be an outdated driver.

Did this work for you? Let us know in the comments below.

3 Comments

  1. Doesn’t address my issue. My screen is being dimmed by Microsoft setting in win 10 and I no longer have access to the brightness slider. It darkens only the right side of the monitor to make it difficult to read the task bar or icon text. It appears to be malicious software behavior that alters win 10 settings that users can no longer access like screen brightness. When I reboot my PC the screen displays a perfect blue color that shows no darkening and after it loads the desk top it darkens the right side of the screen. All my power options are fully enabled and turned on. This isn’t a power issue for my desktop. It’s malware.

  2. Or, …
    Windows Update just fired off another set of downloads and the “dimming and brightening” is the OS trying to get your attention to restart the computer.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.