Your Dell monitor may experience a display or video issue when connected to a Dell laptop through a WD15 or TB16 Dell docking station.
If none of the following articles resolved your issue, there is a new resolution in the following section of this article:
How to Use and Troubleshoot Dell Docking Station WD15
BIOS configuration confirmed
Driver installation path followed
External monitor blanking or flickering on TB16 and WD15 docks
Firmware updates:
Open Device Manager (Right-click the Windows Button and click Device Manager).
Expand the category Network Adapters.
Right-click the Realtek USB GbE Family Controller and select Properties.
Click the Advanced tab.
Select Selective suspend in the menu and set the value to DISABLED.
Click the OK button and reboot the computer.
Video or display issues can be caused due to outdated or corrupt video or GPU drivers.
Updating the computer to the latest version of the Intel Graphics driver resolves the issue. To download and install the latest graphics update:
Browse to the Dell Drivers & Downloads page.
Identify your Dell laptop using the Service Tag, or click Browse all products and select your Dell laptop from the product catalog.
Select the Operating System.
Under Category, select Video.
Locate the latest Intel Graphics Driver.
Click Download and save the file to your computer.
Uninstall the existing Intel Graphics driver from Apps & features in the Windows settings menu and selecting Intel Graphic Diver.
Restart the computer after the uninstall is complete.
Open File Explorer and browse to the location where the downloaded file is saved.
Double-click the graphics setup file and follow the on-screen instructions to complete the installation process.
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