Safety instructions Use the following safety guidelines to protect your monitor from potential damage and to ensure your personal safety. Unless otherwise noted, each procedure included in this document assumes that you have read the safety information that shipped with your monitor. NOTE: Before using the monitor, read the safety instruction that is shipped with your monitor and printed on the product.
About your monitor Package contents The following table provides the list of components that are shipped with your monitor. If any component is missing, contact Dell. For more information, see Contact Dell. NOTE: Some items may be optional and may not ship with your monitor.
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Power cable (varies by country) DisplayPort cable (DP to DP) Cable length: 1.80 M HDMI cable Cable length: 1.80 M USB Type-C cable Cable length: 1.00 M USB-A to USB-C Gen2 Cable Cable length: 1.00 M • Quick Setup Guide •...
Product features The Dell U3423WE monitor has an active matrix, Thin-Film Transistor (TFT), Liquid Crystal Display (LCD) and LED backlight. The monitor features include: • 86.72 cm (34.14 in.) viewable area (measured diagonally). 3440 x 1440 (21:9) resolution, plus full-screen support for lower resolutions.
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• Built-in speakers (5 W) x 2. • Optimize eye comfort with a flicker-free screen and ComfortView Plus feature. • This monitor uses low blue light panel. When the monitor is reset to factory settings or default setting (Preset mode: Standard), it works in compliance with TÜV Rheinland (hardware solutions provider).
Identifying parts and controls Front view Label Description Power LED indicator Solid white light indicates that the monitor is turned on and functioning normally. Blinking white light indicates that the monitor is in Standby Mode. │ About your monitor...
Releases stand from the monitor. Barcode, serial number, and Refer to this label if you need to Service Tag label contact Dell for technical support. Power On/Off button To turn the monitor on or off. Joystick Use to control the OSD menu. (For...
Bottom view Bottom view without monitor stand Label Description Secures the monitor with security lock Security lock slot (security lock not included). (based on Kensington Security Slot™) Power connector Connect the power cable (shipped with your monitor). HDMI port (2) Connect your computer with the HDMI cable.
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Super speed USB 10 Connect the USB Type-C cable that came Gbps (USB 3.2 Gen2) with your monitor to the computer or mobile Type-C upstream port device. This port supports USB Power (video and data) Delivery, Data, and DisplayPort video signal. The super speed USB 10 Gbps (USB 3.2 Gen2) Type-C port offers the fastest transfer rate and the alternate mode with DP 1.4...
Super speed USB 10 Connect your USB device.** Gbps (USB 3.2 Gen2) NOTE: To use this port, you must connect Type-C downstream the USB Type-C cable or USB Type-C to port Type-A Cable (shipped with your monitor) to the USB Type-C upstream port on the monitor and to your computer.
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Response time 8 ms (Normal) 5 ms (Fast) Color depth 1.07 billion colors Color gamut • DCI-P3 98% • Display P3 98% • sRGB 100% • Rec 709 100% DCI-P3, Display P3, sRGB, & Rec 709: Calibration accuracy Delta E < 2 (average) Connectivity •...
NOTE: Do not mount or use this monitor in portrait (vertical) orientation or inverse (180°) landscape mount as it may damage the monitor. Built-in speakers 2 x 5 W sound output Dell Display Manager Easy Arrange and other key features compatibility Security Security lock slot (cable lock sold separately) *DisplayPort and USB Type-C (Alternate mode with DisplayPort 1.4): HBR3/...
Preset display modes Display mode Horizontal Vertical Pixel Sync frequency frequency clock polarity (kHz) (Hz) (MHz) (Horizontal /Vertical) VESA, 720 x 400 31.5 70.1 28.3 VESA, 640 x 480 31.5 59.9 25.2 VESA, 640 x 480 37.5 75.0 31.5 VESA, 800 x 600 37.9 60.3 40.0...
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Inrush current • 120 V: 40 A (Max.) at 0°C (cold start) • 240 V: 80 A (Max.) at 0°C (cold start) Power consumption • 0.3 W (Off mode) • 0.3 W (Standby mode) • 31 W (On mode) • 198 W (Max.) •...
NOTE: Dell monitors are designed to work optimally with the video cables that are shipped with your monitor. As Dell does not have control over the different cable suppliers in the market, the type of material, connector and process used to manufacture these cables, Dell does not guarantee video performance on cables that are not shipped with your Dell monitor.
Weight without stand assembly 7.72 kg (17.01 lb) (For wall mount or VESA mount considerations - no cables) Weight of stand assembly 3.29 kg (7.25 lb) Environmental characteristics Model U3423WE Compliant standards • ENERGY STAR certified monitor • EPEAT registered where applicable. EPEAT registration varies by country. See www.epeat.net for registration status by country.
Pin assignments DisplayPort connector (in) 20-pin side of the number connected signal cable ML3 (n) ML3 (p) ML2 (n) ML2 (p) ML1 (n) ML1 (p) ML0 (n) ML0 (p) AUX (p) AUX (n) Hot Plug Detect Re-PWR +3.3 V DP_PWR │...
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HDMI connector 19-pin side of the number connected signal cable TMDS DATA 2+ TMDS DATA 2 SHIELD TMDS DATA 2- TMDS DATA 1+ TMDS DATA 1 SHIELD TMDS DATA 1- TMDS DATA 0+ TMDS DATA 0 SHIELD TMDS DATA 0- TMDS CLOCK+ TMDS CLOCK SHIELD TMDS CLOCK-...
Universal Serial Bus (USB) interface This section gives you information about the USB ports that are available on the monitor. NOTE: This monitor is super speed USB 10 Gbps (USB 3.2 Gen2) compatible. Transfer speed Data rate Maximum power supported* Super speed 10 Gbps 4.5 W...
SSTX- SSTX+ USB Type-C connector Pin Number Signal Name Pin Number Signal Name TX1+ TX2+ TX1- TX2- VBUS VBUS SBU1 SBU2 VBUS VBUS RX2- RX1- RX2+ RX1+ USB ports • 1 super speed USB 10 Gbps (USB 3.2 Gen2) Type-C upstream (video + data) - bottom •...
NOTE: Super speed USB 10 Gbps (USB 3.2 Gen2) functionality requires a super speed USB 10 Gbps (USB 3.2 Gen2)-capable computer. NOTE: The USB ports on the monitor work only when the monitor is turned On or in Standby mode. If you turn Off the monitor and then turn it On, the attached peripherals may take a few seconds to resume normal functionality.
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Mac Address (Printed on model label) Pass-thru (MAPT), Wake-on-LAN (WOL) from standby mode (S3 only) and UEFI* PXE Boot function [UEFI PXE Boot is not supported on Dell Desktop PC’s (except for OptiPlex 7090/3090 Ultra Desktop)], these 3 features depend on BIOS settings and version of the OS.
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RJ45 Connector LED Status Color Description Right LED Amber or Green Speed indicator: • Amber On - 1000 Mbps • Green On - 100 Mbps • Off - 10 Mbps Left LED Green Link / Activity indicator: • Blinking - Activity on the port. •...
During the LCD Monitor manufacturing process, it is not uncommon for one or more pixels to become fixed in an unchanging state which are hard to see and do not affect the display quality or usability. For more information on Dell Monitor Quality and Pixel Policy, see www.dell.com/pixelguidelines.
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• Adjust the tilt of the monitor, its contrast, and brightness settings. • Adjust the ambient lighting around you (such as overhead lights, desk lamps, and the curtains or blinds on nearby windows) to minimize reflections and glare on the monitor screen. •...
Handling and moving your display To ensure that the monitor is handled safely when lifting or moving it, follow these guidelines: • Before moving or lifting the monitor, turn off your computer and the monitor. • Disconnect all cables from the monitor. •...
For best practices, follow the instructions in the list below when unpacking, cleaning, or handling your monitor: • To clean the Dell monitor screen, lightly dampen a soft, clean cloth with water. If possible, use a special screen-cleaning tissue or solution suitable for the Dell monitor screen.
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Customer Induced Damage (CID). CID is not covered under the standard Dell warranty. • If you notice white powder when you unpack your monitor, wipe it off with a cloth.
Setting up the monitor Attaching the stand NOTE: The stand is not installed at the factory when shipped. NOTE: The following instructions are applicable only for the stand that was shipped with your monitor. If you are attaching a stand that you purchased from any other source, follow the setup instructions that were included with the stand.
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6. Lift the cover, as shown, to access the VESA area for stand assembly. 7. Attach the stand assembly to the monitor. a. Fit the two tabs on the upper part of the stand to the groove on the back of the monitor.
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8. Place the monitor upright. NOTE: Lift the monitor carefully to prevent it from slipping or falling. 9. Remove the cover from the monitor. │ Setting up the monitor...
NOTE: Dell monitors are designed to work optimally with the Dell- supplied cables inside the box. Dell does not guarantee the video quality and performance if non-Dell cables are used. NOTE: Route the cables through the cable-management slot before connecting them.
Connecting the DisplayPort (DisplayPort to DisplayPort) cable Connecting the HDMI cable Connecting the USB Type-C cable NOTE: Use the USB Type-C cable shipped with monitor only. • This port supports DisplayPort Alternate Mode (DP1.4 standard only). • The USB Type-C power delivery compliant port (PD Version 3.0) delivers up to 90 W of power.
• If your notebook requires more than 90 W to operate and the battery is drained, it may not be powered up or charged with the USB PD port of this monitor. Connecting the monitor for RJ45 Cable (Optional) NOTE: RJ45 cable is non in-box standard accessory. Connecting the super speed USB 10 Gbps (USB 3.2 Gen2) cable NOTE: To prevent data damage or loss, before unplugging the USB upstream port, make sure that NO USB storage devices are in use by...
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3. Plug the power cables for your computer(s) and monitor into a nearby outlet. a. Connect one computer b. Connect two computers * When connecting two computers to the monitor, configure the USB settings from the OSD menu to share a single set of keyboard and mouse connected to the monitor between two computers.
Dell Power Button Sync (DPBS) Your monitor is designed with Dell Power Button Sync (DPBS) feature to allow you to control PC system power state from the monitor power button. This feature is only supported with Dell platform which has built-in DPBS function, and is only supported over USB-C interface.
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2. Select Hardware and Sound, followed by Power Options. 3. Go to System Settings. │ Setting up the monitor...
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4. In the drop-down menu of When I press the power button, there are a few options for selection, namely Do nothing/Sleep/Hibernate/Shut down. You can select Sleep/Hibernate/Shut down. NOTE: Do not select “Do nothing”, otherwise the monitor power button will not be able to sync with PC system power state. │...
4. Both the monitor and PC will turn ON normally. If not, press either the monitor power button or PC power button to boot up the system. NOTE: Ensure that Dell Power Button Sync is set to On. See Dell Power Button Sync.
Using DPBS Function Waking on the USB-C cable When you connect the USB-C cable, the Monitor/PC state is as follows: *Not all Dell PC systems support to wake up the platform via the monitor. *Upon USB-C cable connection, mouse movement or keyboard press might be required to wake the system/monitor up from sleep or hibernate.
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NOTE: You can enable or disable the power button sync function via OSD. See Dell Power Button Sync. • When the monitor and the PC power state are both ON, press and hold the monitor power button for 4 seconds, the screen prompt will ask if you would like to shut down the PC.
Connecting the monitor for USB-C If the Dell PC* has two USB-C ports, the power state of each connected monitor will sync with the PC. For example, when the PC and two monitors are in an initial ON power state, pressing the power button on Monitor 1 or Monitor 2 will turn OFF the PC, Monitor 1, and Monitor 2.
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Ensure that Dell Power Button Sync is set to ON (see Dell Power Button Sync). When the PC and two monitors are in an initial OFF power state, pressing the power button on Monitor 1 or Monitor 2 will turn ON the PC, Monitor 1, and Monitor 2.
Securing your monitor using Kensington lock (optional) The security-lock slot is located at the bottom of the monitor (see Security lock slot (based on Kensington Security Slot™)). Secure your monitor to a table using the Kensington security lock. For more information on using the Kensington lock (sold separately), see the documentation that is shipped with the lock.
3. Lift the stand assembly up and away from the monitor. VESA wall mounting (optional) (Screw dimension: M4 x 10 mm). Refer to the instructions that come with the VESA-compatible wall mounting kit. 1. Place the monitor panel on a soft cloth or cushion on a stable flat table. 2.
Operating the monitor Power on the monitor Press the Power Button to turn On the monitor. Using the Joystick Control Use the joystick control on the rear of the monitor to make OSD adjustments. 1. Press the joystick button to launch the OSD main menu. 2.
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Joystick Description • When the OSD menu is on, press the button to confirm the selection or save the settings. • When the OSD menu is off, press the button to launch the OSD main menu. See Accessing the menu system.
Select this icon to adjust the brightness and contrast level. Shortcut key/ Brightness/Contrast Select this icon to set PIP/PBP. Shortcut key/ PIP/PBP Select this icon to switch between the USB upstream sources in PIP/PBP mode. Shortcut key/ USB Switch Select this icon to set the Input Source. Shortcut key/ Input Source Select this icon to launch the On-Screen Display...
Using the On-Screen Display (OSD) menu Accessing the menu system NOTE: After you change the settings, press the joystick to save the changes before proceeding to another menu or exit the OSD menu. Icon Menu and Description Submenus Brightness/ Use this menu to activate Brightness/Contrast Contrast adjustment.
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Input Source Use the Input Source menu to select between the different video signals that may be connected to your monitor. USB-C Select the USB-C 90W input when you are using the USB Type-C connector. Press the joystick to confirm the selection. Select the DP input when you are using the DisplayPort (DP) connector.
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Auto Select for Allows you to set Auto Select for USB-C to: USB-C • Prompt for Multiple Inputs: Always displays the “Switch to USB-C Video Input” message for you to choose whether to switch or not. • Yes: Always switches to USB-C video input (without asking) when the USB Type-C cable is connected.
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Preset Modes Allows you to choose from a list of preset color modes. • Standard: Loads the monitor's default color settings. This is the default preset mode. • Movie: Loads color settings ideal for movies. • Game: Loads color settings ideal for most gaming applications.
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Preset Modes NOTE: When you select DCI-P3 as the color space, the luminance of the backlight defaults to 48 cd/m (typical). You can manually adjust the luminance of the backlight by using the Brightness function under Brightness/Contrast in the OSD menu. •...
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Saturation This feature can adjust the color saturation of the video image. Toggle the joystick up or down to adjust the saturation from '0' to '100'. NOTE: Saturation adjustment is available only when you select Movie or Game preset mode. Reset Color Resets your monitor’s color settings to the factory settings.
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Uniformity Select screen uniformity compensation settings. On Compensation is factory calibrated setting by default. Uniformity Compensation adjusts different areas of the screen with respect to the center to achieve uniform brightness and color over the entire screen. For optimal screen performance, Brightness and Contrast for some preset modes (Standard, Color Temp.) will be disabled when Uniformity Compensation is turned On.
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Dell Power Turns the Dell Power Button Sync feature On or Off. Button Sync When Off is selected, power button sync function will be disabled. NOTE: When Off is selected, the Wake-on-Connect function will remain active. Reset Display Resets all display settings to the factory preset values.
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PIP/PBP Mode Adjusts the PIP/PBP (Picture in Picture/Picture by Picture) mode to (50% - 50%), (74% - (PIP1 small), 26%), (26% - 74%), (PIP2 small), (PIP3 small), (PIP4 (PIP2 large), small), (PIP1 large), (PIP3 large), or (PIP4 large). You can disable this feature by selecting Off.
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Allows you to assign the USB upstream port for the input signals (DP, HDMI 1, and HDMI 2), thus the monitor's USB downstream port (eg. keyboard and mouse) can be used by the current input signals when you connect a computer to either one of the upstream ports.
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Show KVM Select this option and follow steps if you want to Setup Guide connect multiple computers to the monitor and use one setup of keyboard and mouse. Reset USB Resets all settings under the USB menu to the factory preset values. Audio Volume Allows you to set the volume level of speakers.
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Menu Select this option to adjust the settings of the OSD, such as, the languages of the OSD, the amount of time the menu remains on screen, and so on. Language Sets the OSD display to one of the eight languages (English, Spanish, French, German, Brazilian Portuguese, Russian, Simplified Chinese, or Japanese).
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Lock With the control buttons on the monitor locked, you can prevent people from accessing the controls. It also prevents accidental activation in multiple monitors side-by-side setup. • Menu Buttons: All joystick functions are locked and not accessible by the user. •...
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Personalize Shortcut Key 1 Allows you to choose a feature from Preset Modes, Shortcut Key 2 Brightness/Contrast, Input Source, Aspect Shortcut Key 3 Ratio, PIP/PBP Mode, USB Switch, Ethernet Switch, Video Swap, Volume, or Display Info and Shortcut Key 4 set it as a shortcut key.
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Others Select this option to adjust the OSD settings, such as DDC/CI, LCD Conditioning, and so on. Display Info Displays the monitor's current settings. DDC/CI DDC/CI (Display Data Channel/Command Interface) allows your monitor parameters (brightness, color balance, and etc.) to be adjustable via the software on your computer.
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Displays the firmware version of your monitor. Service Tag Displays the service tag of your monitor. This string is required when you look for phone support, check your warranty status, update drivers on Dell's website, etc. Self-Diagnostic Press the joystick to initiate the self-diagnostic process.
Factory Reset Restore all preset values to the factory default settings. These are also the settings for ENERGY ® STAR tests. OSD warning message When the monitor does not support a particular resolution mode, you will see the following message: This means that the monitor cannot synchronize with the signal that it is receiving from the computer.
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You will see the following message before the DDC/CI function is disabled: When you adjust the Brightness level for the first time, the following message appears: NOTE: If you select Yes, the message will not appear the next time you change the Brightness setting.
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NOTE: If you select Yes for any one of the features mentioned above, the message will not appear next time when you intend to change the settings of these features. When you perform a factory reset, the message will appear again. You will see the following message before the Lock function is activated: NOTE: The message may be slightly different according to the selected settings.
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Activate the computer and the monitor to gain access to the OSD. NOTE: The message may be slightly different according to the connected input signal. If either USB Type-C, DisplayPort, or HDMI input is selected and the corresponding cable is not connected, a floating dialog box as shown below appears. NOTE: The message may be slightly different according to the connected input signal.
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When Yes is selected, the following messages appear. │ Operating the monitor...
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When you switch the USB Switch from PC 1 to PC 2, and Ethernet Switch Mode is set to Prompt then KVM switches, the following message appears: NOTE: When ‘No, and do not ask again’ is selected, Ethernet Switch Mode will change to ‘Switch Manually’. When ‘Yes, and do not ask again’...
Depending on your computer, complete one of the following procedures: If you have a Dell desktop or laptop: • Go to https://www.dell.com/support, enter your service tag, and download the latest driver for your graphics card. If you are using a non-Dell computer (laptop or desktop): •...
Setting the KVM switch The built-in KVM switch allows you to control up to 2 computers from a single set of keyboard and mouse connected to the monitor. a. When connecting HDMI + USB-C (data only) to computer 1 and DP + USB-C (video and data) to computer 2: NOTE: The USB Type-C connections currently only support data transfer.
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b. When connecting HDMI + USB-C (data only) to computer 1 and USB-C (video and data) to computer 2: NOTE: The USB-C (video and data) connection currently supports video and data transfer. Make sure USB for HDMI is assigned to USB-C2 NOTE: As the USB Type-C (video and data) port supports the DisplayPort Alternate Mode, there is no need to set USB for USB-C.
Setting the Auto KVM You can follow below instruction to set up Auto KVM for your monitor: 1. Ensure that PIP/PBP Mode is Off. 2. Ensure that Auto Select is On and Auto Select for USB-C is Yes. │ Operating the monitor...
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3. Ensure that the USB ports and the video inputs are paired accordingly. NOTE: For USB Type-C (video and data) connection, there is no further setting required. │ Operating the monitor...
Using the tilt, swivel, vertical extension, and slant adjust NOTE: The following instructions are applicable only for attaching the stand that was shipped with your monitor. If you are attaching a stand that you purchased from any other source, follow the set up instructions that were included with the stand.
Slant adjust With the stand attached to the monitor, you can adjust the monitor to your desired angle with the slant adjust feature. │ Operating the monitor...
Troubleshooting WARNING: Before you begin any of the procedures in this section, follow the Safety instructions. Self-test Your monitor provides a self-test feature that allows you to check whether your monitor is functioning properly. If your monitor and computer are properly connected but the monitor screen remains dark, run the monitor self-test by performing the following steps: 1.
Using the joystick to lock/unlock buttons Locking the power and joystick buttons You can lock the joystick and power buttons to prevent access to the OSD menu and/or power off the monitor. To lock the buttons: 1. Toggle and hold the joystick to the up or down or left or right for about 4 seconds until a pop menu appears.
You may verify your current firmware revision in Firmware. If this is not available, go to the Dell download support site for the latest application installer (Monitor Firmware Update Utility.exe) and refer to the Firmware Update Instruction User's Guide: www.dell.com/U3423WE.
Common problems The following table contains general information about common monitor problems you might encounter and the possible solutions: Common What you Possible solutions symptoms experience No Video/Power No picture • Ensure that the video cable LED off connecting the monitor and the computer is properly connected and secure.
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• Cycle power On-Off. spots • Pixel that is permanently Off is a natural defect that can occur in LCD technology. • For more information on Dell Monitor Quality and Pixel Policy, see Dell Support site at: http:// www.dell.com/pixelguidelines. Stuck-on Pixels LCD screen has •...
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Safety Related Visible signs of • Do not perform any troubleshooting Issues smoke or sparks steps. • Contact Dell immediately. Intermittent Monitor • Ensure that the video cable Problems malfunctions on & connecting the monitor to the computer is connected properly and is secure.
Image retention Faint shadow • Set the screen to turn off after a few from a static from the static minutes of screen idle time. These can image left on the image displayed be adjusted in Windows Power monitor for a long appears on the Options or Mac Energy Saver setting.
No video at HDMI/ When connected to • Unplug the HDMI/DisplayPort/USB some dongle/ DisplayPort/USB Type-C cable from dongle/docking docking device at Type-C port device, then plug the docking HDMI/ the port, there is no DisplayPort/USB Type-C cable to the video when notebook.
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USB Type-C port USB peripherals • Check that the connected device is does not supply can not be charged compliant with the USB-C power specification. The USB Type-C port supports USB 3.2 Gen2 and an output of 90 W. • Check that you use the USB Type-C cable shipped with your monitor.
Speakers Specific Problems Specific What You Possible Solutions Symptoms Experience No sound Cannot hear • Turn Off the monitor, unplug the monitor coming from any sound power cord, replug it, and then turn On the the external monitor. speakers • Ensure the audio cable is connected correctly between the Audio Line Out port and the external speaker.
Regulatory information FCC notices (U.S. only) and other regulatory information For FCC notices and other regulatory information, see the regulatory compliance website located at www.dell.com/regulatory_compliance. EU product database for energy label and product information sheet U3423WE: https://eprel.ec.europa.eu/qr/1264609 │ Regulatory information...
Contact Dell To contact Dell for sales, technical support, or customer service issues, see www.dell.com/contactdell. NOTE: Availability varies by country and product, and some services may not be available in your country. NOTE: If you do not have an active Internet connection, you can find contact information on your purchase invoice, packing slip, bill, or Dell product catalog.