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Dell D2421H Monitor Usage and Troubleshooting Guide

Summary: Learn how to setup and use Dell D2421H monitor. Find troubleshooting instructions for common video or display issues.

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Instructions

D2421H productshot

Quick Links

Getting Started with your Dell D2421H monitor Dell D2421H monitor Setup, Specifications and Service Manual Dell Drivers & Downloads Warranty and Support Services Frequently asked questions

For help with video or display issues such as: no video or no display, blank or black screen, flickering, resolution or color issues, horizontal or vertical lines, etc. refer to an expanding section below.

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The key features of Dell D2421H monitor are:

  • 60.5 cm (23.8 in.) diagonal viewable image size, 1920 x 1080 resolution, plus full-screen support for lower resolutions.
  • Arsenic-free glass and Mercury-free for the panel only.
  • Plug and play capability if supported by your system.
  • Ultrathin bezel minimizes bezel gap in multimonitor setup
  • Tilt, swivel, height, and rotating adjustment
  • 0.5 W standby power when in the sleep mode
  • Optimize eye comfort with a flicker-free screen
WARNING: The possible long-term effects of blue light emission from the monitor may damage your eyes, including eye fatigue or digital eye strain. ComfortView feature is designed to reduce the amount of blue light that is emitted from the monitor to optimize eye comfort.
 
WARNING: Do not mount this monitor in vertical orientation due to the risk of damaging the monitor.

This section provides some specifications of the Dell D2421H monitor. To learn more about the specifications of Dell D2421H monitor, refer to the User's Guide at the Dell Manuals website.

Panel technology
  • In-Plane Switching
Maximum resolution
  • 1920 x 1080 at 60 Hz
Viewing angle
  • 178° (vertical) typical
  • 178° (horizontal) typical
Contrast ratio
  • 1000 to 1 (typical)
Response time
  • 8 milliseconds (Normal)
  • 5 milliseconds (Fast)
Color gamut
  • 72% NTSC(CIE 1931) and 83% NTSC(CIE 1976)
Color depth
  • 16.7 million colors
Ports and connectors
  • 2 x HDMI 2.0 (HDCP 2.2) (10-bit color @ 60 Hz)
  • 1 x DP 1.4 (HDCP 2.2) (10-bit color @ 60 Hz)
  • 1 x USB Type-C (Alternate mode with DP1.4, Power Delivery, and USB2.0) (8-bit color @ 60 Hz)
  • 2 x USB 3.0 upstream port
  • 5 x USB 3.0 Downstream port

Ensuring that your Dell monitor is set up properly. Assembling the monitor stand and setting up the monitor ergonomically. Connecting the cables and organizing them. These will only help make the viewing experience the best it possibly can be.

Attaching the stand

The standard monitor stand is detached when the monitor is shipped from the factory. To learn more about attaching the standard monitor stand. Refer to the Setting Up the Monitor section in the User's Guide of your Dell D2421H monitor.
To learn how to set up any other stand with a monitor, refer to the respective stand setup guide for setup instructions.

CAUTION: Do not remove the monitor from the packaging box before attaching the stand.
 
NOTE: The Dell D2421H monitor is very heavy; handle with extreme care. It is recommended to have two people to lift or move this monitor.

Ergonomics

Where you put your monitor is almost as important as what model you buy. The monitor should be directly in front of you, at an arm’s length away (between 20-40 inches from your eyes). The top edge of the screen at eye level when you are sitting comfortably. You may need to adjust your chair height or the height of the monitor to achieve this.

Connecting your monitor to the PC

To connect your Dell D2421H monitor to your PC:

  1. Turn off your PC and disconnect the power cable.
  2. Connect the DisplayPort, HDMI, or USB Type-C cable to the corresponding video or display port on the back of your PC.
    NOTE: Dell D2421H supports display over USB Type-C port with Alternate mode DP 1.4. Ensure that the USB Type-C on your PC supports Alternate mode DP 1.2 or above.

    To learn more about connecting your monitor to the PC, refer to the Dell knowledge-base article: How do I connect a monitor to a PC?

  3. Connect the USB upstream cable to the monitor and PC.

Dell D2421H monitor orientation must always be in landscape mode. This includes any wall-mounted monitors and monitors on a stand. In a multiple monitor setup, Dell D2421H should not be rotated either to 180° (landscape) or 90° (portrait).

CAUTION: Dell D2421H setup must comply to the recommended panel orientation and working angle only. Setting up the monitor in an orientation that is not recommended may damage the monitor and/or cause a safety hazard.

When setting up your Dell D2421H monitor, ensure that the monitor front panel buttons is on the bottom right.

Using the Tilt, Swivel, and Vertical Extension
NOTE: This is applicable for a monitor with a stand. When any other stand is bought, please refer to the respective stand setup guide for set-up instructions.

With the stand attached to the monitor, you can tilt and swivel the monitor for the most comfortable viewing angle.

HOW17581_en_US__7I_Dell_D2421H_vertical_extension_CH_v1
Figure 5: Using Tilt and Swivel on Dell D2421H monitor

When mounted on the wall or on a monitor arm, the set-up must comply to the recommended panel orientation and working angle.

HOW17581_en_US__8I_Dell_D2421H_Orientation_CH_v1
Figure 6: Orientation of Dell D2421H

Use the buttons at the bottom of the monitor to access the On-Screen Display (OSD) menu of the monitor. To access the On-Screen Display (OSD) menu, press Button 5 (Figure 1) at the bottom of the monitor.

Learn more about using the On-Screen Display (OSD) menu. Refer to the Operating Your Monitor section in the User's Guide of Dell D2421H monitor.

NOTE: Any changes that you make are automatically saved. Whenever you move to another menu item, exit the OSD menu, or wait for the OSD menu to automatically close.

HOW17581_en_US__11I_Dell_D2421H_Front_Panel_Navigation_Buttons_CH_V1
Figure 1: Dell D2421H Front Panel Buttons
Button Function Description
Button 1 Menu Use this button to launch the on-screen display (OSD), go back to the main menu, or exit the OSD main menu.
Button 2 DOWN Use this button to select the next item down the list or decrease the setting value.
  • When not in OSD menu, directly enters Contrast/Brightness
Button 3 UP Use this button to select the next item up the list or increase the setting value.
  • When not in OSD menu, directly enters Color Vision Mode.
Button 4 Input Source
  • When not in OSD menu, directly enters Input Source from a list of VGA, HDMI, Auto (D2421H/D2721H).
  • When not in OSD menu, directly enters Input Source from a list of HDMI1, HDMI2, HDMI3, DP, Auto (D2421DS).
Button 5 Power On/Off button. Power button to turn the monitor On and Off.
6 Power LED The blue LED indicates the monitor is On and fully functional.

Resetting a monitor to factory defaults can help resolve many video or display issues. To reset your Dell D2421H monitor to factory default settings, follow these instructions:

  1. Press Button 5 (Figure 2) on the monitor to enter the On-Screen Display (OSD) Menu.
  2. Press Button 3 or Button 4 to highlight Others option in the menu and press Button 5 to select.
  3. Press Button 3 or Button 4 to highlight Factory Reset option in the menu and press Button 5 to select.
  4. Press Button 5 to confirm the reset action.

HOW17581_en_US__11I_Dell_D2421H_Front_Panel_Navigation_Buttons_CH_V1
Figure 2: Dell D2421H Front Panel Buttons

If your Dell monitor has a blank or black screen, fuzzy or blurry image, flickering, distorted or any other screen abnormalities, running a diagnostic test will help determine if the Dell monitor is functioning normally. To learn more about diagnostic options on a Dell monitor, refer to the Dell knowledge-base article: How do I run diagnostics on a Dell monitor?

It is always essential to isolate the monitor while troubleshooting your computer for the following scenarios:

  • No Power - Your computer is not powering ON or showing any signs of power.
  • No POST - Your computer is not showing any indication of activity, the screen might be blank and will not display the Dell logo during start-up.
  • No Video - You are unable to see any display on the screen, able to hear the windows chime but no display is seen.

Your Dell D2421H Monitor provides a self-test feature check that allows you to check whether the monitor is functioning properly. If the monitor and computer are properly connected but the monitor screen remains dark, run the monitor self-test by performing the following steps:

  1. Turn off both your computer and the monitor.
  2. Unplug the video cable from the back of the computer. To ensure proper Self-Test operation, remove the video cables (VGA, DVI, HDMI, or DisplayPort) from the back of the computer.
  3. Turn on the monitor.
  4. Turn off your monitor and reconnect the video cable: then turn on both your computer and the monitor.
  5. If your monitor screen remains blank after you use the previous procedure, check your video card (GPU) and computer, because your monitor is functioning properly.

Your Dell D2421H monitor has a built-in diagnostic tool. It helps to determine if the screen abnormality you are experiencing is a problem with the monitor or with the video card on your computer.

How to Run the Dell D1918H, D2421H, D2421DS, and D2721H Monitor Self Test

During the LCD Monitor manufacturing process, it is not uncommon for one or more pixels to become fixed in an unchanging state. Which is hard to see and do not affect the display quality or usability. For more information, refer to the Dell knowledge-base article Dell LCD Monitor Pixel Guidelines.

This section provides information about troubleshooting steps that can help resolve the most common issues with the Dell D2421H monitor. Alternatively, to learn more about troubleshooting common issues on Dell monitors, refer to the Dell knowledge-base article Troubleshooting Display or Video Issues on a Dell Monitor.

 

Common Problem What User Experiences Possible Solution
No Video - Power LED Off No picture
  • Make sure that the power cable connecting the monitor is properly connected and secure.
  • Verify that the power outlet is functioning properly using any other electrical equipment.
  • Make sure that the power button is depressed fully.
  • Test with known good cable and known good system if possible.
No Video - Power LED On No picture or no brightness.
  • Increase the brightness and contrast of the monitor through On-Screen Display Menu (OSD).
  • Perform monitor self-test feature check.
  • Check for bent or broken pins in the video cable connector.
  • Reseat both ends of video cable.
  • Try with known good video cable.
  • Run the built-in diagnostics.
  • Make sure that the correct input source is selected via the Input Source Select button.
  • Test monitor with known good system if available.
Poor Focus Picture is fuzzy, blurry, or ghosting.
Shaky or Jittery Video Wavy picture or fine movement.
Missing Pixels LCD screen has spots.
  • Cycle power on-off.
  • Pixel that is permanently off is a natural defect that can occur in LCD technology.
  • Run the built-in diagnostics.
Stuck-On/Off Pixels LCD screen has bright spot.
Brightness Problems Picture too dim or too bright.
Geometric Distortion Screen not centered correctly.
NOTE: When using DisplayPort input, the positioning adjustments are not available.
Horizontal or Vertical Lines Screen has one or more lines.
NOTE: When using DisplayPort input, the positioning adjustments are not available.
Synchronization Problems Screen is scrambled or appears torn.
  • Reset the monitor to the Factory Settings.
  • Perform Auto Adjust via On-Screen Display Menu (OSD).
  • Adjust Phase and Pixel Clock controls via On-Screen Display Menu (OSD).
  • Perform monitor self-test feature check to determine if the scrambled screen appears in self-test mode.
  • Check for bent or broken pins in the video cable connector.
  • Restart the computer in the power safe mode.
Safety-Related Issues Visible signs of smoke or sparks.
  • Do not perform any troubleshooting steps.
  • Contact Dell Technical Support immediately.
Intermittent Problems Monitor malfunctions on and off.
  • Make sure that the video cable is connected properly with the monitor and the computer.
  • Reset the monitor to the Factory Settings.
  • Run the self-test feature and determine if the intermittent problem occurs in the self-test mode.
Missing Color Picture does not have color.
  • Run the monitor self-test feature check.
  • Make sure that the video cable connecting the monitor to the computer is connected properly and is secure.
  • Check for bent or broken pins in the video cable connector.
Wrong Color Picture color is not good.
Image Retention from a Static Image Left on the Monitor for a Long Period Faint shadow from the static image appears on the screen.
  • Use the Power Management feature to turn off the monitor when it is not in use.
  • Alternatively, use a dynamically changing screensaver.
Screen image is too small. Image is centered on screen, but does not fill entire viewing area.
Image Ghosting Fast moving images leave a trail of shadow images.

On certain video and applications with fast moving images, imaging ghosting, which appears as a trailing shadow, may occur.

Change the Response Time to Fast in the Display menu.
No Input Signal when user controls are pressed. No picture, the power LED light is white.
  • Check the signal source. Ensure that the computer is not in power-saving mode by moving the mouse or pressing any key on the keyboard.
  • Make sure that the video cable is connected properly with the monitor and the computer.
  • Restart the computer.
The picture does not fill the entire screen. The picture cannot fill the height or width of the screen.
  • Due to different video formats (aspect ratio) of DVDs and videos, the monitor may display in screen.
  • Run the built-in diagnostics.
No Video, No Display No video when connecting docking, dongle, or Blu-ray DVD players Due to legacy platform cannot recognize or output 5120 x 1440, we suggest changing EDID to lower resolution to cover this compatibility problem.
  1. Remove all input cables, press Button 3 and Button 4 for 5 seconds.
  2. Choose Enable on POP up screen to change max resolution from 5120 x 1440 to 3840 x 1080
Unable to switch back to native resolution (5120 x 1440) after Picture by Picture is turned off.

Dell D2421H supports Picture by Picture (PBP) mode. Picture by Picture (PBP) mode is 2 side-by-side images with each image that is displayed at 2560 x 1440 resolution.

When the monitor is connected to a PC via HDMI and PBP mode is turned off, the monitor may display images at the lower resolution (2560 x 1440) rather than automatically switching to the native resolution (5120 x 1440).
  1. Disconnect the HDMI cable
  2. Wait for 5-10 seconds
  3. Connect the HDMI cable
Display mode changes from "Second screen only" to "Extended mode" after opening and closing the laptop LCD.

The display mode on your PC reverts to "Duplicate" or "Extend,". This depends on which was selected before you changed to "Second screen only" or "Projector only" when you close and open the laptop screen.

When you close and then reopen the lid on a laptop, the Connecting and Configuring Displays (CCD) feature in Windows automatically reverts the display mode to the last active selection. This behavior is by design in Microsoft Windows.

Switch to the display mode that you want after you close and reopen the laptop screen manually:

  1. Press the Windows logo key + P on the keyboard
  2. Select Second screen only or Projector only mode
Monitor blinks twice when connected to PC with NVIDIA NVS 310 video or graphics card.

When the monitor is turned-off and back on, the monitor may blink twice. This issue may occur if the PC is using a NVIDIA Graphic NVS 310 card and graphics card resolution setting is 2560 x 1600.

To resolve this issue, manually set the resolution to 2560 x 1440 using the NVIDIA Control Panel.

  1. Right-click on the desktop and select NVIDIA Control Panel
  2. In the NVIDIA Control Panel, select Change resolution in the left panel
  3. Under Resolution, select 2560 x 1440
  4. Click Apply to confirm
Monitor has sound icon when Dell D2421H is connected to a laptop using HDMI.

Dell D2421H does not support audio or sound via HDMI. Speakers or headphones must be connected via the audio connector on the PC.

To resolve the audio icon displaying, update the video or graphics (GPU) driver to the latest version. To learn how to download and update a device driver, refer to the Dell knowledge-base article How do I download and install a device driver?
Monitor will not display Blu-Ray video after the monitor is powered-off and powered on. If the monitor is powered-off and powered-on when displaying the Blu-Ray video, the Blu-ray player may lose the data signal from the system to the monitor.
  1. Disconnect the HDMI cable
  2. Wait for 5 seconds
  3. Connect the HDMI cable
Cannot enable YCbCr color mode on the monitor. When monitor is connect to the PC via HDMI, the video or graphics card (GPU) controls the YCbCr setting Disable the YCbCr setting from the video or graphics utility like Intel HD Graphics Control Panel.
Monitor will not support the YCbCr color format when a USB Type-C to HDMI dongle is connected from the monitor to the PC. Some combinations of USB Type-C to HDMI dongle and video or graphics card (GPU) are not compatible to support the YCbCr color format.
  • Do not use the dongle
  • Connect the computer to the monitor via the HDMI cable or the USB-C cable
  • Disable the YCbCr setting from the video or graphics card (GPU) utility like Intel HD Graphics Control Panel
When changing the monitor’s resolution from Windows Display Settings, the image quality may not be good. Windows Display Settings and the resolution settings on the laptop's video or graphics utility may not be compatible. Change the resolution using the video or graphics card (GPU) utility like Intel HD Graphics Control Panel.
No video when the monitor is connected to a Dell docking station. The monitor may not receive video signals from the PC when connected to a Dell docking station. To learn more about how to set up and configure the Dell D2421H monitor with a Dell docking station. Refer to the Dell knowledge-base article Dell D2421H - System Requirements and Supported Configuration.
Light leak from the monitor The monitor appears to have light leak from the edges in a dark room This is normal behavior of the monitor. Dell consumer monitors are inspected at 150-lux ambient lighting (similar to typical office lighting). Dell UltraSharp and Gaming monitors are inspected with a tighter criteria of 70-lux ambient lighting (dimly lit room but not dark).
Color variation on the corners of the monitor The monitor appears to have color variation on the corners of the screen

The optimal viewing position for the monitor is from the center of the screen.

Dell D2421H monitor uses a curved IPS panel, the corners of the screen may appear slight yellowish or pinkish, especially when viewing in dark room. This is normal IPS panel behavior and typically does not affect the overall viewing performance.

  1. Change the Uniformity Compensation via On-Screen Display Menu (OSD).
  2. Change the Uniformity compensation setting to Calibrated
No video when a Blu-Ray, DVD player or PS4 is connected to the monitor via HDMI. The monitor does not display any video when an external Blu-ray, DVD player or PS4 is connected.

Dell D2421H monitor is factory default set at HDMI EDID with 3 Block (Detailed Timing Descriptor) to support 5120 x 1440 @ 60 Hz. To display a resolution of 3840 x 1080 @ 60 Hz or lower, you need to switch the monitor HDMI EDID from 3 Block to 2 Block.

  1. Remove all input cables from the monitor
  2. Press and hold Button 3 and Button 4 for 5 seconds
  3. A message box will appear. Select Enable to switch to lower primary resolution

To display 5120 x 1440 resolution over HDMI again, you need to switch the monitor back to HDMI EDID 3 Block. Follow Steps 1 & 2, and Select Disable.
Horizontal stripes when watching online videos using Microsoft Movies and TV app, Microsoft Internet Explorer or Microsoft Edge. Unwanted horizontal stripes appear on the video playback window when viewing online videos on YouTube using Microsoft Internet Explorer or Microsoft Edge browser. They are also seen while watching online videos using the Movies and TV app.
  • Change the monitor resolution to 4k 3840 x 1080 or lower.
  • For YouTube videos, change the playback resolution to 720p or lower.
 
Troubleshooting USB Issues
Specific Symptoms What User Experiences Possible Solution
USB interface is not working. USB peripherals are not working.
  • Check that your monitor is turned On.
  • Reconnect the upstream cable to your computer.
  • Reconnect the USB peripherals (downstream connector).
  • Switch Off and then turn On the monitor again.
  • Reboot the computer.
  • Some USB devices like external portable HDD require higher electric current; connect the device directly to the computer.
High-Speed USB 3.0 interface is slow. High-Speed USB 3.0 peripherals working slowly or not working at all
  • Check that your computer is USB 3.0 capable.
  • Some computers have USB 3.0, USB 2.0 and USB 1.1 ports.
  • Ensure that the correct USB port is used.
  • Reconnect the upstream cable to your computer.
  • Reconnect the USB peripherals (downstream connector).
  • Reboot the computer.
Wireless USB peripherals stop working when a USB 3.0 device is plugged in. Wireless USB peripherals responding slowly or only working as the distance between itself and its receiver decreases.
  • Increase the distance between the USB 3.0 peripherals and the wireless USB receiver.
  • Position your wireless USB receiver as close as possible to the wireless USB peripherals.
  • Use a USB-extender cable to position the wireless USB receiver as far away as possible from the USB 3.0 port.
USB Type-C port does not supply power. USB peripherals cannot be charged.
  • Check that the connected device is compliant with the USB-C specification. The USB Type-C port supports USB 3.1 with speeds up to 10 Gbps and an output of 90 W.
  • Ensure you use the USB Type-C cable shipped with your monitor.
USB ports on the monitor do not work when the monitor is connected to a PC using USB Type-C. If the monitor is powered-off and powered-on too quickly, the laptop will not recognize the system change.
  1. Power off the monitor
  2. Wait for 5 seconds
  3. Power on the monitor
Monitor does not wake up via the USB keyboard or mouse that is connected to the monitor. In sleep mode, the monitor does not receive power to the USB 3.0 ports. Wake up the laptop PC using the built-in keyboard or touchpad

To learn more about how to view or download the User Guides and Manuals for your Dell product. Refer to the Dell knowledge-base article Manuals and Documentation for your Dell Product.


Frequently asked questions

Using Windows Display Settings

In Windows 10, Windows 8 or 8.1 and Windows 7:

  1. For Windows 8 and Windows 8.1 only, select the Desktop tile to switch to classic desktop view.
  2. Right-click on the desktop and click Screen Resolution.
  3. Click the dropdown list of the Screen Resolution and select 5120 x 1440.
  4. Click OK

Using NVIDIA Control Panel

To change the resolution using the NVIDIA Control Panel:

  1. Right-click on the desktop and click NVIDIA Control Panel.
  2. Click the + symbol next to Display on the left pane.
  3. Select Change Resolution under Display.
  4. In the dropdown menu on the right pane, select the resolution 5120 x 1440.
  5. Click Apply.

Using AMD Catalyst Control Center

To change the resolution using the AMD Catalyst Control Center:

  1. Right-click on the desktop and click AMD Catalyst Control Center.
  2. Click the + symbol next to Display on the left pane.
  3. Select Change Resolution under Display.
  4. In the dropdown menu on the right pane, select the resolution 5120 x 1440.
  5. Click Apply.
NOTE: If you do not see the recommended resolution as an option. You may need to update the video card (GPU) driver by visiting the Dell Drivers & Downloads website or the video card (GPU) manufacturers website. To learn how to download and update a device driver, refer to the Dell knowledge-base article: How do I download and install a device driver?

To reset the Dell D2421H Monitor to factory defaults, refer to the Reset to Factory Settings section of this article.

The Dell D2421H monitor has two built-in diagnostics that are available:

  • Self-Test Feature Check - The self-test feature check on the Dell D2421H monitor allows you to check whether the monitor is functioning properly.
  • Built-In Self-Test - The Dell D2421H monitor has a built-in self-test that helps you identify if the screen abnormality is with the monitor or the video card (GPU) on your computer. When you notice screen abnormalities like distortion, clarity, horizontal or vertical lines, color fade. It is always a good practice to isolate the monitor by running the Built-In Diagnostics.

To learn how to run a diagnostic test, refer to the Running Diagnostics on Dell D2421H Monitor section of this Dell knowledge-base article.

The Troubleshooting section of this Dell knowledge-base article provides information about troubleshooting common issues with the Dell D2421H monitor. The section has troubleshooting steps on how to resolve power issues, video issues, color or clarity issues, distortion issues, horizontal or vertical lines, brightness issues or pixel issues and so on.

To navigate the On-Screen Display (OSD) menu, use the buttons on the monitor. The monitor control buttons are usually on the right side, either on the side, front, or bottom of the monitor. To access the On-Screen Display (OSD) menu, press Button 5 on the monitor.

For more information about using the On-Screen Display (OSD) menu and different menu options. Refer to the Operating Your Monitor section in the User's Guide of your Dell D2421H monitor.

.

Additional monitor information like the model number, firmware version and Service Tag can be accessed from the monitor's OSD (On-Screen Display).

  1. Press Button 5 (Figure 2) on the monitor to enter the On-Screen Display (OSD) Menu.
  2. Press Button 3 or Button 4 to highlight Others option in the menu and press Button 5 to select.
  3. Press Button 3 or Button 4 to highlight Model Number or Firmware Version option in the menu and press Button 5 to select.
  4. Press Button 6 to exit the OSD menu.

Dell D2421H supports both DisplayPort 1.4 connectivity with your PC. If the video or graphics card (GPU) on your PC supports DisplayPort 1.2, it is required to change the monitor to DisplayPort 1.2 mode.

NOTE: The default factory setting on the Dell D2421H is DisplayPort 1.4 (DP1.4).
  1. Press Button 5 (Figure 4) on the monitor to enter the On-Screen Display (OSD) Menu
  2. Press Button 3 or Button 4 to highlight Input Source in the menu and press Button 5 to select.
  3. Press Button 3 or Button 4 to highlight DP in the menu.
  4. Press and hold Button 5 for approximately 10 seconds until the DisplayPort configuration message appears.
  5. Press Button 5 to select Disable and change the display mode to DisplayPort version 1.2

HOW17581_en_US__11I_Dell_D2421H_Front_Panel_Navigation_Buttons_CH_V1
Figure 4: Dell D2421H Front Panel Buttons

Dell D2421H supports both HDMI 2.0 and HDMI 1.4 connectivity with your PC. If the video or graphics card (GPU) on your PC supports HDMI 1.4, it is required to change the monitor to HDMI 1.4 mode.

NOTE: The default factory setting on the Dell D2421H is HDMI 2.0.
  1. Press Button 5 (Figure 4) on the monitor to enter the On-Screen Display (OSD) Menu
  2. Press Button 3 or Button 4 to highlight Input Source in the menu and press Button 5 to select.
  3. Press Button 3 or Button 4 to highlight HDMI in the menu.
  4. Press and hold Button 5 for approximately 10 seconds until the HDMI configuration message appears.
  5. Press Button 5 to select Disable and change the display mode to HDMI version 1.4

HOW17581_en_US__11I_Dell_D2421H_Front_Panel_Navigation_Buttons_CH_V1
Figure 4: Dell D2421H Front Panel Buttons

USB Type-C port on your Dell D2421H supports USB Power Delivery, Data, and DisplayPort video signal. The USB Type-C port can be used for video and data signal, and supply power (90 W) to a compatible laptop PC using a single USB Type-C cable that is provided with the monitor.

NOTE: Dell D2421H can supply power via the USB Type-C cable only to a compatible laptop PC that supports Power Delivery (PD) over USB Type-C. Not all laptop PCs with USB Type-C support Power Delivery, for more information refer to the User Manual or contact your laptop manufacturer.
NOTE: USB Type-C power delivery-compliant port (PD version 2.0) delivers up to 90 W of power. If your laptop PC requires more than 90 W to operate and the battery is drained. It is recommended you use the standard AC adapter of the laptop PC to power on and charge the laptop battery.

If you are using a Dell laptop PC that supports charging via USB Type-C. It is recommended to update the BIOS and Video or Graphics card (GPU) driver. To learn how to download and update a device driver, refer to the Dell knowledge-base article: How do I download and install a device driver?

Dell D2421H monitor orientation must always be in landscape mode. This includes any wall-mounted monitors and monitors on a stand. In a multiple monitor setup, Dell D2421H should not be rotated either to 180° (landscape) or 90° (portrait).

CAUTION: Dell D2421H setup must comply to the recommended panel orientation and working angle only. Setting up the monitor in an orientation that is not recommended may cause.

When setting up your Dell D2421H monitor, ensure that the monitor front panel buttons is on the bottom right.

Using the Tilt, Swivel, and Vertical Extension
NOTE: This is applicable for a monitor with a stand. When any other stand is bought, please refer to the respective stand setup guide for set-up instructions.

With the stand attached to the monitor, you can tilt and swivel the monitor for the most comfortable viewing angle.

HOW17581_en_US__7I_Dell_D2421H_vertical_extension_CH_v1
Figure 5: Using Tilt and Swivel on Dell D2421H monitor

When mounted on the wall or on a monitor arm, the set-up must comply to the recommended panel orientation and working angle.

HOW17581_en_US__8I_Dell_D2421H_Orientation_CH_v1
Figure 6: Orientation of Dell D2421H

Affected Products

Dell D2421H
Article Properties
Article Number: 000181565
Article Type: How To
Last Modified: 30 Nov 2021
Version:  5
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