Cannot Adjust the LCD Brightness on XPS 15 7590 Laptops

Cannot change the LCD brightness setting

You may not be able to adjust the LCD brightness when you update the BIOS version to 1.5.0 on your XPS 15 7590 laptop.

Open Device Manager to confirm if you find multiple entries under the Monitors. (See Figure.1)

(Figure.1 Device Manager)

None of the following methods allow you to increase or decrease the brightness at this point:

• Using either the Fn + up (F2) or the Fn + down key (F3) keyboard shortcuts to adjust the brightness.
• Adjusting the brightness from the Display Settings or the Windows Mobility Center. (See Figure.2) The value can be adjusted, but the display is stuck at a certain brightness. There is no effect if you adjust it to 0 or 100.

(Figure.2 Windows Mobility Center)

• Updating to the latest version of the Video Driver on the laptops Drivers & Downloads page.

This is not a hardware issue. The following steps take you through resolving this issue:

1. Open the Device Manager utility on your laptop.

   Type Device Manager into your Start Menu and select the application from the search results.

2. Expand the Monitors category.

   Click the chevron to open and close the tree function.

3. Uninstall all the monitors listed.

   Right click on each monitor in the list and select uninstall from the menu that appears.

4. Reboot your laptop.

5. After it reboots, only one entry is listed under Monitors in Device Manager.

Adjust the brightness in the Windows Setting again to confirm the issue is resolved.