How to Troubleshoot Multiple Monitor Issues

Summary: Learn how to troubleshoot multiple monitor issues. Find information on common troubleshooting steps to resolve display issues when using multiple monitors

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Learn how to troubleshoot display issues like monitor not detected, no display error message, when using multiple monitors connected to the PC

If you are trying to setup multiple monitors, refer to the Dell knowledge-base article:



It is essential to verify if the problem is inherent with the monitor, video card (GPU) or video settings on your PC. A straightforward way to identify this is to connect the PC to a known-good external monitor or TV and ensure that the display (S-video, VGA, DVI, HDMI or DisplayPort) cables are firmly connected to the video ports on the PC and the monitor.

To learn more about connecting your Dell PC to a monitor or TV, refer to the Dell knowledge-base article How do I Connect a Monitor or TV to a PC?.

Performance issues may occur if there is any type of damage caused to the display cables or the LCD screen. LCD screen may show symptoms like LCD screen stops working, work intermittently, color mismatch, flickering, display horizontal or vertical lines, etc. if there is a damage to the display cables or the LCD screen.

If you do notice a physical damage, contact Dell Technical Support to learn more about repair options that are available in your region. If there is no damage, proceed to the next step.

Dell monitors provide a self-test feature check (STFC) and a built-in self test (BIST) diagnostic tool that helps determine if the screen abnormality you are experiencing is an inherent problem with the Dell monitor or with the video card (GPU) and PC settings.

When you notice screen abnormalities like flickering, distortion, clarity issues, fuzzy or blurry image, horizontal or vertical lines, color fade etc, it is always a good practice to isolate the monitor by running a diagnostic check on the Dell monitor.

To learn more about running a diagnostic check on your Dell monitor, refer to the Dell knowledge-base article How do I Run Diagnostics on a Dell Monitor?

SLN151719_en_US__1icon Note: Self test feature check (STFC) helps check if the Dell monitor is functioning normally as a stand-alone device. To check for screen abnormalities like flickering, distortion, clarity issues, fuzzy or blurry image, horizontal or vertical lines, color fade etc.
SLN151719_en_US__1icon Note: Built-in self test (BIST) can be run only when the video cable(s) is unplugged and the Dell monitor is in self-test mode.

To reset a Dell monitor to factory default settings, follow these instructions:

  1. Press Button 3 on the monitor to enter the On-Screen Display (OSD) Menu.
  2. Press Button 1 or Button 2 to highlight Others option in the menu and press Button 3 to select.
  3. Press Button 1 or Button 2 to highlight Factory Reset option in the menu and press Button 3 to select.
  4. Press Button 3 to confirm the reset action.
SLN151719_en_US__1icon Note: Reset instructions for your Dell monitor may vary slightly, refer to the User Guide of your Dell monitor at the Dell Manuals website.

Dell recommends updating the device drivers and BIOS as part of your scheduled update cycle. These device drivers and BIOS updates may contain feature enhancements or changes that will help keep your system software current and compatible with other system modules (hardware and software) as well as increased stability.

It is essential to update the following device drivers for optimal video performance and to resolve common video issues:

  • BIOS
  • Chipset driver
  • Video Card (GPU) driver
  • Monitor driver

To learn more about downloading and installing a device driver on a Dell PC, refer to the Dell knowledge-base article How do I update the device drivers on a Dell PC?.

Windows updates can support your Windows operating system in many ways. Windows updates can solve specific problems, provide protection from malicious attacks, or even add new features to the operating system.

How to run Windows Updates on Microsoft Windows 10?

  1. Right-click Start and click Settings.
  2. In the Settings panel, click Update & Security.
  3. In the left panel, select Windows Update.
  4. On the right panel, click Check for updates.
  5. Restart the PC after downloading and installing the updates.

Display settings like refresh rate, resolution and power management may affect the performance of your Dell monitor. Changing the display settings can help resolve several types of video issues.

To learn more about changing the brightness, refresh rate and resolution on a Dell PC, refer to the Dell knowledge-base article How do I Change Common Video Settings in Microsoft Windows?.

System Restore is a built-in Windows tool designed to protect and repair the operating system. When something goes wrong with your PC, System Restore should be used prior to restoring the PC to factory defaults.

Select the Operating System installed on your PC to find more information about how to perform System Restore:

General Information

To learn about different types of video ports or connectors on a Dell PC, refer to the Dell knowledge-base article Guide to Ports, Connectors, and Cables on Dell PCs or How do I connect a monitor to a PC?.


Frequently asked questions

  • Microsoft Windows 10
  • Microsoft Windows 8 or 8.1
  • Microsoft Windows 7

For the best experience, it is recommended to have multiple monitors of the same specification (monitor size and maximum supported resolution). You may connect monitors of different size and resolution if to an available video port on the PC.

Most laptop PCs support one external monitor that can be connected to an available video port (VGA, DVI, HDMI or DisplayPort). Refer to the User Manual of your PC to learn how many multiple monitors it can support at the same time.

Docking stations or port replicators allow you to connect multiple monitors and other peripherals to the PC.

SLN151719_en_US__1icon Note: Some laptop PCs may only allow the laptop LCD to be the primary monitor.

Yes, you can connect a TV to the PC as a secondary monitor. The video port or connector on your PC must match with an available video port or connector on the TV. While most TVs come with HDMI, some TVs also support VGA connectivity to a PC.

Yes, you will still be able to use them in a multiple monitor setup. However, both monitors will work in their individual supported resolution and one monitor may be bigger or smaller in size than the other.

For the best viewing experience, it is recommended to have monitors of the same specifications.

Microsoft Windows 10 by default supports multiple monitor configuration. Windows 10 can extend the ‘Taskbar’ to all the connected monitors by default with full Windows menu integration.

There are four display modes available in Microsoft Windows 10, which can be accessed by pressing Windows logo + P key on the keyboard.

SLN151719_en_US__1icon Note: Display mode shortcut Windows logo + P key can be used in Windows 10, Windows 8 or 8.1 and Windows XP operating systems.
  • PC Screen only: Windows will only use your primary monitor, and any additional monitors will be black.
  • Duplicate: Windows will show the same image on all monitors. This is useful if you’re giving a presentation and want the same image on your primary monitor and the secondary display, for example.
  • Extend: Windows will enlarge and extend your desktop, giving you another screen to work with. This is the option you’ll want if you’re using an additional monitor for additional PC screen space.
  • Second screen only: Windows will turn off your primary display and only use the secondary display.

You may also use the graphics card utility that is installed on your PC to configure multiple monitors. Depending on the video or graphics card installed in your PC, you may have one of the following utilities:

  • Intel Graphics Control Panel or Intel HD Graphics
  • AMD Catalyst Control Center
  • Nvidia Control Panel

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Last Published Date

21 Feb 2021



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