Dell P2421 User manual

Dell P2421 Monitor
User’s Guide
Model: P2421
Regulatory model: P2421b

NOTE: A NOTE indicates important information that helps you make
better use of your computer.
CAUTION: A CAUTION indicates potential damage to hardware or loss
of data if instructions are not followed.
WARNING: A WARNING indicates a potential for property damage,
personal injury, or death.
Copyright © 2020 Dell Inc. or its subsidiaries. All rights reserved. Dell, EMC, and other trademarks
are trademarks of Dell Inc. or its subsidiaries. Other trademarks may be trademarks of their respective
owners.
2020 - 05
Rev. A00

│  3
Contents
About your monitor . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Package contents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Product features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Identifying parts and controls . . . . . . . . . . . . . . . . . . . . . . 9
Front view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Back view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Side view. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Bottom view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Monitor specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Resolution specifications. . . . . . . . . . . . . . . . . . . . . . . . . 14
Supported video modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Preset display modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Electrical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Physical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Environmental characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Power management modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Pin assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Plug and play capability . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Universal Serial Bus (USB) interface . . . . . . . . . . . . . . . . 24
USB 3.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
USB 2.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
USB 3.0 upstream connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
USB 3.0 downstream connector . . . . . . . . . . . . . . . . . . . . . . . . . . 25
USB 2.0 downstream connector . . . . . . . . . . . . . . . . . . . . . . . . . . 26
USB ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
LCD monitor quality and pixel policy . . . . . . . . . . . . . . . . 26

4  │ 
Maintenance guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Cleaning your monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Setting up the monitor . . . . . . . . . . . . . . . . . . . . . . 28
Attaching the stand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Connecting your monitor . . . . . . . . . . . . . . . . . . . . . . . . . 31
Connecting the DisplayPort (DisplayPort to DisplayPort) cable. . 31
Connecting the HDMI cable (optional) . . . . . . . . . . . . . . . . . . . . . 32
Connecting the VGA cable (optional) . . . . . . . . . . . . . . . . . . . . . . 32
Connecting the DVI cable (optional) . . . . . . . . . . . . . . . . . . . . . . . 32
Connecting the USB 3.0 cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Organizing your cables. . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Removing the monitor stand . . . . . . . . . . . . . . . . . . . . . . 34
VESA wall mounting (optional) . . . . . . . . . . . . . . . . . . . . 34
Operating the monitor . . . . . . . . . . . . . . . . . . . . . . 36
Power on the monitor. . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Using the front-panel controls. . . . . . . . . . . . . . . . . . . . . 36
Front-panel button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Using the On-Screen Display (OSD) menu . . . . . . . . . . . 38
Accessing the menu system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
OSD warning message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Setting the maximum resolution . . . . . . . . . . . . . . . . . . . 54
Using the tilt, swivel, and vertical extension . . . . . . . . . . 55
Tilt, swivel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Vertical extension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Rotating the monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Rotate clockwise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Rotate counterclockwise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Adjusting the rotation display settings of your system . . 58

│  5
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Self-test. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Built-in diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Common problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Product specific problems . . . . . . . . . . . . . . . . . . . . . . . . 66
Universal Serial Bus (USB) specific problems . . . . . . . . . 67
Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
FCC notices (U.S. only) and other regulatory
information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Contact Dell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

6  │  About your monitor
About your monitor
Package contents
Your monitor ships with the components shown in the table below. If any
component is missing, contact Dell technical support. For more information, see
Contact Dell.
NOTE: Some items may be optional and may not ship with your monitor.
Some features may not be available in certain countries.
NOTE: If you are attaching a stand that you purchased from any other
source, follow the set up instructions that were included with the
stand.
Display
Stand riser
Stand base

About your monitor  │  7
Power cable (varies by
country)
DisplayPort cable
(DisplayPort to DisplayPort)
VGA cable (Japan only)
USB 3.0 upstream cable
(enables the USB ports on
the monitor)
• Quick Setup Guide
• Safety, Environmental,
and Regulatory
Information

8  │  About your monitor
Product features
The Dell P2421 monitor has an active matrix, Thin-Film Transistor (TFT), Liquid
Crystal Display (LCD) and LED backlight. The monitor features include:
• 61.13 cm (24.1 in.) viewable area (measured diagonally).
1920 x 1200 (16:10) resolution, plus full-screen support for lower resolutions.
• Wide viewing angle to allow viewing from a sitting or standing position.
• Color gamut of 99% sRGB.
• Digital connectivity with DVI, DisplayPort and HDMI.
• Tilt, swivel, height, and rotate adjustment capabilities.
• Removable stand and Video Electronics Standards Association (VESA™)
100 mm mounting holes for flexible mounting solutions.
• Equipped with 1 USB upstream port and 4 USB downstream ports.
• Plug and play capability if supported by your system.
• On-Screen Display (OSD) adjustments for ease of set-up and screen
optimization.
• Power and OSD buttons lock.
• Security lock slot.
• Stand lock.
• 0.3 W standby power when in sleep mode.
• Optimize eye comfort with a flicker-free screen.
WARNING: The possible long-term effects of blue light emission from
the monitor may cause damage to the eyes, including eye fatigue,
digital eye strain, and so on. ComfortView feature is designed to reduce
the amount of blue light emitted from the monitor to optimize eye
comfort.

About your monitor  │  9
Identifying parts and controls
Front view
Front panel controls
Label Description
1Function buttons (For more information, see Operating the monitor)
2Power On/Off button (with LED indicator)

10  │  About your monitor
Back view
Back view with monitor stand
Label Description Use
1VESA mounting holes (100 mm
x 100 mm - behind attached
VESA Cover)
Wall mount monitor using VESA-
compatible wall mount kit (100 mm x
100 mm).
2Regulatory label Lists the regulatory approvals.
3Stand release button Releases stand from the monitor.
4Barcode, serial number, and
Service T
ag label
Refer to this label if you need to
contact Dell for technical support.
5Cable-management slot Use to organize cables by inserting
them through the slot.

About your monitor  │  11
Side view
Label Description Use
1USB 3.0 downstream ports (2) Connect your USB device.
NOTE: T
o use these ports, you must
connect the USB cable (shipped with
your monitor) to the USB-upstream
port on the monitor and to your
computer.

12  │  About your monitor
Bottom view
Bottom view without monitor stand
Label Description Use
1Security lock slot Secures the monitor with security lock
(security lock not included).
2Power connector Connect the power cable (shipped with your
monitor).
3DisplayPort Connect your computer with the DisplayPort
cable (shipped with your monitor).
4HDMI port Connect your computer with the HDMI cable.
5Stand lock feature To lock the stand to the monitor using a M3 x
6mm screw (screw not included).
6DVI port Connect your computer with the DVI cable.
7VGA connector Connect your computer with the VGA cable
(shipped with your monitor, for Japan only).
8USB 3.0 upstream port Connect the USB cable (shipped with your
monitor) to this port and your computer to
enable the USB ports on your monitor.
9USB 2.0 downstream
port (2)
Connect your USB device.
NOTE: T
o use this port, you must connect the
USB cable (shipped with your monitor) to the
USB-upstream port on the monitor and to
your computer.

About your monitor  │  13
Monitor specifications
Model P2421
Screen type Active matrix - TFT LCD
Panel technology In-Plane Switching Technology
Aspect ratio 16:10
Viewable image
Diagonal
Width (active area)
Height (active area)
To t a l a re a
611.3 mm (24.10 in.)
518.4 mm (20.41 in.)
324.0 mm (12.76 in.)
167961.6 mm2(260.34 in.2)
Pixel pitch 0.270 mm x 0.270 mm
Pixel per inch (PPI) 94
Viewing angle 178° (vertical) typical
178° (horizontal) typical
Luminance output 300 cd/m² (typical)
Contrast ratio 1000 to 1 (typical)
Faceplate coating AG type, 3H hard coating, Haze 25
Backlight White LED edgelight system
Response time 8 ms (Normal)
5 ms (Fast)
Color depth 16.7 million colors
Color gamut 99% sRGB
Built-in devices • USB 3.0 Super-Speed hub (with 1 x USB 3.0
upstream port)
• 2 x USB 3.0 downstream ports
• 2 x USB 2.0 downstream ports

14  │  About your monitor
Resolution specifications
Model P2421
Horizontal scan range 30 kHz to 83 kHz (automatic)
Vertical scan range 56 Hz to 76 Hz (automatic)
Maximum preset resolution 1920 x 1200 at 60 Hz
Supported video modes
Model P2421
Video display capabilities (VGA
& DVI & HDMI & DisplayPort
playback)
480p, 480i, 576p, 576i, 720p, 1080i, 1080p,
Connectivity • 1 x DisplayPort version 1.2
•1xHDMIportversion1.4
•1xDVIport
•1xVGAport
•1xUSB3.0upstreamport
• 2 x USB 3.0 downstream ports
• 2 x USB 2.0 downstream ports
Border width (edge of
monitor to active area)
6.3 mm (Top)
6.3 mm (Left/Right)
19.2 mm (Bottom)
Adjustability
Height adjustable stand
Ti l t
Swivel
Pivot
130 mm
-5° to 21°
-45° to 45°
-90° to 90°
Dell Display Manager
compatibility
Easy Arrange and other key features
Security Security lock slot (cable lock sold separately)

About your monitor  │  15
Preset display modes
Display mode Horizontal
frequency
(kHz)
Vertical
frequency
(Hz)
Pixel
clock
(MHz)
Sync
polarity
(Horizontal
/Vertical)
VESA, 720 x 400 31.5 70.1 28.3 -/+
VESA, 640 x 480 31.5 60.0 25.2 -/-
VESA, 640 x 480 37.5 75.0 31.5 -/-
VESA, 800 x 600 37.9 60.3 40.0 +/+
VESA, 800 x 600 46.9 75.0 49.5 +/+
VESA, 1024 x 768 48.4 60.0 65.0 -/-
VESA, 1024 x 768 60.0 75.0 78.8 +/+
VESA, 1152 x 864 67.5 75.0 108.0 +/+
VESA, 1280 x 1024 64.0 60.0 108.0 +/+
VESA, 1280 x 1024 80.0 75.0 135.0 +/+
VESA, 1600 x 1200 75.0 60.0 162.0 +/+
VESA, 1920 x 1080 67.5 60.0 148.5 +/+
VESA, 1920 x 1200 74.0 60.0 154.0 +/+

16  │  About your monitor
Electrical specifications
Model P2421
Video input signals • Analog RGB, 0.7 V ± 5%, positive polarity at 75 Ω input
impedance
• Digital DVI-D TMDS, 600 mV for each differential line,
positive polarity at 50 Ω input impedance
• HDMI 1.4, 600 mV for each differential line, 100 Ω input
impedance per differential pair
• DisplayPort 1.2, 600 mV for each differential line, 100 Ω
input impedance per differential pair
AC input voltage/
frequency/current
100 VAC to 240 VAC / 50 Hz or 60 Hz ± 3 Hz / 1.2 A
(typical)
Inrush current • 120 V: 30 A (Max.) at 0°C (cold start)
• 240 V: 60 A (Max.) at 0°C (cold start)
Physical characteristics
Model P2421
Signal cable type • Digital: DisplayPort, 20 pins
• Digital: HDMI, 19 pins (cable not included)
• Digital: DVI-D, 24 pins (cable not
included)
• Analog: D-Sub, 15 pins (cable not
included, except for Japan)
• Universal Serial Bus: USB, 9 pins
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.
Dimensions (with stand)
Height (extended) 500.8 mm (19.72 in.)

About your monitor  │  17
Height (compressed) 370.8 mm (14.60 in.)
Width 531.0 mm (20.91 in.)
Depth 166.0 mm (6.54 in.)
Dimensions (without stand)
Height 349.5 mm (13.76 in.)
Width 531.0 mm (20.91 in.)
Depth 44.1 mm (1.73 in.)
Stand dimensions
Height (extended) 400.8 mm (15.78 in.)
Height (compressed) 353.4 mm (13.91 in.)
Width 206.0 mm (8.11 in.)
Depth 166.0 mm (6.54 in.)
Base 206.0 mm x 166.0 mm (8.11 in. x 6.54 in.)
Weight
Weight with packaging 7.3 kg (16.1 4 l b)
Weight with stand assembly and
cables
5.6 kg (12.26 lb)
Weight without stand assembly
(For wall mount or VESA mount
considerations - no cables)
3.5 kg (7.63 lb)
Weight of stand assembly 1.6 kg (3.53 lb)
Front frame gloss 2-4 (only front chin)

18  │  About your monitor
Environmental characteristics
Model P2421
Compliant standards
• ENERGY STAR certified monitor
• EPEAT registered where applicable. EPEAT registration varies by country. See
www.epeat.net for registration status by country.
• RoHS-compliant
• TCO certified displays
• BFR/PVC free monitor (excluding external cables)
• Arsenic-free glass and Mercury-free for the panel only
Te m p e r at u re
Operating 0°C to 40°C (32°F to 104°F)
Non-operating • Storage: -20°C to 60°C (-4°F to 140°F)
• Shipping: -20°C to 60°C (-4°F to 140°F)
Humidity
Operating 20% to 80% (non-condensing)
Non-operating • Storage: 10% to 90% (non-condensing)
• Shipping: 10% to 90% (non-condensing)
Altitude
Operating 5000 m (16404 ft) (maximum)
Non-operating 12192 m (40000 ft) (maximum)
Thermal dissipation • 143.3 BTU/hour (maximum)
• 54.6 BTU/hour (typical)

About your monitor  │  19
Power management modes
If you have VESA's DPM™ compliance display card or software installed on your
computer, the monitor can automatically reduce its power consumption when not in
use. This is referred to as Power Save Mode*. If the computer detects input from
the keyboard, mouse, or other input devices, the monitor automatically resumes to
function. The following table shows the power consumption and signaling of this
automatic power saving feature.
VESA
modes
Horizonta
l sync
Vertical
sync
Video Power
indicator
Power
consumption
Normal
operation
Active Active Active White 42 W
(maximum)**
16 W (typical)
Active-off
mode
Inactive Inactive Blanked White
(breathing)
Less than 0.3 W
Switch off - - - Off Less than 0.3 W
Power Consumption Pon 12.2 W
Total Energy Consumption (TEC) 39.1 kWh
*Zero power consumption in OFF mode can only be achieved by disconnecting the
main cable from the monitor.
**Maximum power consumption with max luminance, and USB active.
This document is informational only and reflects laboratory performance. Your
product may perform differently, depending on the software, components and
peripherals you ordered and shall have no obligation to update such information.
Accordingly, the customer should not rely upon this information in making decisions
about electrical tolerances or otherwise. No warranty as to accuracy or
completeness is expressed or implied.
NOTE: This monitor is ENERGY STAR certified.
This product qualifies for ENERGY STAR in the factory
default settings which can be restored by “Factory Reset”
function in the OSD menu. Changing the factory default
settings or enabling other features may increase power
consumption that could exceed the ENERGY STAR specified
limit.

NOTE:
Pon: Power consumption of On mode as defined in Energy Star 8.0
version.
TEC: Total energy consumption in kWh as defined in Energy Star 8.0
version.
20  │  About your monitor
Pin assignments
DisplayPort connector
Pin
number
20-pin side of the connected signal
cable
1ML3 (n)
2GND
3ML3 (p)
4ML2 (n)
5GND
6ML2 (p)
7ML1 (n)
8GND
9ML1 (p)
10 ML0 (n)
11 GND
12 ML0 (p)
13 GND
14 GND
15 AUX (p)
16 GND
17 AUX (n)
18 Hot Plug Detect