Table of Contents
- Safety instructions
- About your monitor
- Setting up the monitor
- Operating the monitor
- Troubleshooting
- Appendix
- Outline dimension
DELL S2721HN User Manual
Displayed below is the user manual for S2721HN by DELL which is a product in the Computer Monitors category. This manual has pages.
Related Manuals
Model: S2421HN/S2721HN/S2421NX/S2721NX
Regulatory model: S2421Ht/S2721Ht
Dell S2421HN/S2721HN/S2421NX/
S2721NX Monitor
User’s Guide
NOTE: A NOTE indicates important information that helps you make
better use of your monitor.
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 – 07
Rev. X00
Contents
Safety instructions.......................... 5
About your monitor ......................... 6
Package contents . . . . . . . . . . . . . . . . . . . . . . 6
Product features . . . . . . . . . . . . . . . . . . . . . . .7
Identifying parts and controls . . . . . . . . . . . . . . . .8
Front view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Back view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Bottom view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Monitor specifications . . . . . . . . . . . . . . . . . . . 11
Resolution specifications . . . . . . . . . . . . . . . . . . . . . . 12
Preset display modes . . . . . . . . . . . . . . . . . . . . . . . . 13
Electrical specifications. . . . . . . . . . . . . . . . . . . . . . . 13
Physical characteristics. . . . . . . . . . . . . . . . . . . . . . . 14
Environmental characteristics . . . . . . . . . . . . . . . . . . . 15
Power management modes . . . . . . . . . . . . . . . . . . . . . 16
Pin Assignments. . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Plug-and-play . . . . . . . . . . . . . . . . . . . . . . . 19
LCD monitor quality and pixel policy . . . . . . . . . . . 19
Ergonomics. . . . . . . . . . . . . . . . . . . . . . . . . 19
Handling and moving your display . . . . . . . . . . . . . 21
Maintenance guidelines . . . . . . . . . . . . . . . . . . 22
Cleaning your monitor. . . . . . . . . . . . . . . . . . . . . . . . 22
Contents | 3
4 | Contents
Setting up the monitor.......................23
Connecting the stand . . . . . . . . . . . . . . . . . . . 23
Using the tilt . . . . . . . . . . . . . . . . . . . . . . . . 26
Connecting your monitor . . . . . . . . . . . . . . . . . 27
Organizing your cables . . . . . . . . . . . . . . . . . . 28
Securing your monitor using Kensington lock (optional) 28
Removing the monitor stand . . . . . . . . . . . . . . . 29
Wall mounting (Optional) . . . . . . . . . . . . . . . . . 30
Operating the monitor .......................31
Power on the monitor . . . . . . . . . . . . . . . . . . . 31
Using the front panel controls. . . . . . . . . . . . . . . 31
Using the OSD lock function . . . . . . . . . . . . . . . 33
Front-panel button . . . . . . . . . . . . . . . . . . . . . 35
Using the On-Screen Display (OSD) menu . . . . . . . . 36
Accessing the menu system . . . . . . . . . . . . . . . . . . . . 36
OSD warning messages . . . . . . . . . . . . . . . . . . . . . . . 47
Setting the maximum resolution . . . . . . . . . . . . . . . . . . 49
Troubleshooting ........................... 50
Self-test . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Built-in diagnostics . . . . . . . . . . . . . . . . . . . . 51
Common problems . . . . . . . . . . . . . . . . . . . . . 52
Product specific problems. . . . . . . . . . . . . . . . . 54
Appendix................................. 55
FCC notices (U.S. only) and other regulatory information 55
Contacting Dell. . . . . . . . . . . . . . . . . . . . . . . 55
Outline dimension ......................... 56
Safety instructions | 5
Safety instructions
CAUTION: Use of controls, adjustments, or procedures other than those
specified in this documentation may result in exposure to shock, electrical
hazards, and/or mechanical hazards.
• Place the monitor on a solid surface and handle it carefully. The screen is fragile
and can be damaged if dropped or hit sharply.
• Always be sure that your monitor is electrically rated to operate with the AC
power available in your location.
• Keep the monitor in room temperature. Excessive cold or hot conditions can have
an adverse effect on the liquid crystal of the display.
• Do not subject the monitor to severe vibration or high impact conditions. For
example, do not place the monitor inside a car trunk.
• Unplug the monitor when it is going to be left unused for an extended period of
time.
• To avoid electric shock, do not attempt to remove any cover or touch the inside
of the monitor.
For information on safety instructions, see the Safety, Environmental, and Regulatory
Information (SERI).
6 | About your monitor
About your monitor
Package contents
Your monitor ships with the components shown below. Ensure that you have received
all the components and see Contacting Dell if anything is missing.
NOTE: Some components may be optional and may not ship with your
monitor. Somefeatures may not be available in certain countries.
Display
S2421/S2721 HN S2421/S2721 NX Stand riser
S2421/S2721 HN S2421/S2721 NX Stand base
S2421/S2721 HN S2421/S2721 NX VESA cover
Power cable (varies by country)
About your monitor | 7
HDMI cable
Dell S2421HN(NX)/S2721HN(NX)
HDMI2HDMI1
HDMIHDMI
1
2
3
4
HDMI
HDMIMI
HDMI
H
DMI
3
2
1
746.A3E01.0001
(DELL P/N: PNF73 rev.X01)
© 2020 Dell Inc. or its subsidiaries.
2020-07
i
www.dell.com/contactdell
6
5° 21°
i
Dell.com/S2421HN/NX
Dell.com/S2721HN/NX
5
3
12
12
12
4
HDMI
Dell S2421H/S2721H
HDMI2HDMI1
HDMIHDMI
1
2
3
4
HDMI
HDMIMI
HDMI
HDMI
3
2
1
746.A3E01.0001
(DELL P/N: PNF73 rev.X01)
© 2020 Dell Inc. or its subsidiaries.
2020-07
i
www.dell.com/contactdell
6
5°21°
i
Dell.com/S2421H
Dell.com/S2721H
5
3
12
12
12
4
HDMI
•Quick Setup Guide
•Safety, Environmental, and
Regulatory Information
Product features
The Dell S2421HN/S2421NX/S2721HN/S2721NX monitor has an active matrix,
Thin Film Transistor (TFT), Liquid Crystal Display (LCD), and LED backlight. The
monitor features include:
• S2421HN/S2421NX: 60.45 cm (23.8 in.) active area display (Measured
diagonally) 1920 x 1080 (16:9) resolution, plus full-screen support for lower
resolutions.
• S2721HN/S2721NX: 68.6 cm (27 in.) active area display (Measured diagonally)
1920 x 1080 (16:9) resolution, plus full-screen support for lower resolutions.
• Tilt adjustment capability.
• Removable pedestal and Video Electronics Standards Association (VESA™) 100
mm mounting holes for flexible mounting solutions.
• Ultra-thin bezel minimizes the bezel gap in multi-monitor usage, enabling easier
set up with an elegant viewing experience.
• Extensive digital connectivity with HDMI helps future-proof your monitor.
• Plug and play capability if supported by your system.
• On-Screen Display (OSD) adjustments for ease of set-up and screen
optimization.
• Supports AMD FreeSyncTM technology. AMD Freesync™ certified range from
48HZ -75HZ.
• Power and OSD buttons lock.
• Security lock slot.
• 0.3 W standby power when in the standby 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 or digital eye
strain. ComfortView feature is designed to reduce the amount of blue light
emitted from the monitor to optimize eye comfort.
About your monitor | 9
Back view
5
3
4
2
1
DELL S2421HN
Flat Panel Monitor / 液晶显示器
型号 : S2421HN
Input Rating / 输入电源 :
100-240V ~ 50/60Hz 1.5A
Made in China / 制造地:中国
Manufactured date / 制造日期:
E
t
DELL S2421HN
Flat Panel Monitor / Monitor Plano Panel / Moniteur à écran plat / 液晶顯示器
Model No. / N° de Modelo / Num éro de modèl e /型號: S2421Ht
Input Rating / Entrada / Daya Tegangan / Tension d’entrée: 100-240V ~ 50/60Hz 1.5A
輸入電源:交流電壓 100-240伏特, 1.5安培, 50/60赫茲
Удельная мощность рабочего режима -X,XXX Вт/см2
Потребляемая мощность изделием в режиме ожидания -X,XX Вт
Потребляемая мощность изделием в выключенном режиме - X,XX Вт
Made in China / Fabricado en China / Fabriqué en Chine / Сделано в Китае / 製造地:中國
警語:使用過度恐傷害視力
신청인: Wistron Corporation (For Korea)
Wistron InfoComm (Zhongshan) Corporation Linhai Branch
제조자: Wistron InfoComm (Zhongshan) Corporation Linhai Branch
A/S 연락처: 080-854-0066
제조국: 중국
CAN ICES-3 (B)/NMB-3(B)
Apparatet må tilkoples jordet stikkontakt.
Apparaten skall anslutas till jordat uttag.
Apparatets stikprop skal tilsluttes en stikkontakt med jord,
som giver forbindelse til stikproppens jord.
Laite on liitettävä suojakoskettimilla varustettuun pistorasiaan.
Consumo de energía en operación: XX.XX Wh
XXXXX
Address for EU Only:
Raheen Business Park
Limerick Ireland
www.dell.com/regulatory_compliance
XXXXXXXX-XXXXX
R-R-WT1-S2421Ht
И005-20
This device complies with part 15 of the FCC Rules.
Operation is subject to the following two conditions:
(1) this device may not cause harmful interference, and
(2) this device must accept any interference received,
including interference that may cause undesired operation.
XXXXXX-XX
IS 13252 (Part 1)/
IEC 60950-1
R-41071650
www.bis.gov.in
For UK only: Cain Road, Bracknell, RG12 1LF
ID XXXXXXXXXX
ID
XXXXXXXXXX
DELL S2421HN
Flat Panel Monitor / 液晶显示器
型号 : S2421HN
Input Rating / 输入电源 :
100-240V ~ 50/60Hz 1.5A
Made in China / 制造地:中国
Manufactured date / 制造日期:
E
t
S2421HN/S2721HN
3
4
2
1
5
S2421NX/S2721NX
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 Release stand from monitor.
4Barcode, serial number, and
Service Tag label
Refer to this label if you need to contact
Dell for technical support. The Service Tag
is a unique alphanumeric identifier that
enables Dell service technicians to identify
the hardware components in your display
and access warranty information.
5Cable management slot Use to organize cables by placing them
through the slot.
10 | About your monitor
Bottom view
21 3 4 5
S2421HN/S2721HN
21 3 4 5
S2421NX/S2721NX
Label Description Use
1Security lock slot Secures monitor with security cable lock (sold
separately).
2Power connector Connect the power cable (shipped with your monitor).
3HDMI port 1 Connect your computer with HDMI cable.
4HDMI port 2 Connect your computer with HDMI cable.
5Audio Line-out port Connect speakers to playback audio coming through
HDMI audio channel.
Only two-channel audio is supported.
NOTE: The audio line-out port does not support
headphones.
About your monitor | 11
Monitor specifications
Model S2421HN/S2421NX S2721HN/S2721NX
Screen type Active matrix - TFT LCD
Panel Type In-plane switching Technology
Aspect ratio 16:9
Viewable image dimensions
Diagonal 60.45 cm (23.8 in.) 68.6 cm (27 in.)
Active Area
Horizontal 527.0 4 mm (20.75 in.) 597.89 mm (23.54 in.)
Vertical 296.46 mm (11.67 in.) 336.31 mm (13.24 in.)
Area 156246.28 mm2 (242.15 in.2) 201073.02 mm2 (311.67 in.2)
Pixel pitch 0.2745 mm x 0.2745 mm 0.3114 mm x 0.3114 mm
Pixel per inch (PPI) 92.56 81.59
Viewing angle
Horizontal 178° (typical)
Vertical 178° (typical)
Brightness 250 cd/m² (typical) 300 cd/m² (typical)
Contrast ratio 1000 to 1 (typical)
Display screen coating Anti-glare treatment of the front polarizer (3H) hard coating
Backlight LED edgelight system
Response Time
(Gray to Gray)
8 ms (normal)
5 ms (fast)
4 ms (extreme)
Color depth 16.7 million colors
Color gamut* NTSC 72%
Connectivity •2 x HDMI 1.4
•1 x Audio line-out(3.5 mm jack)
Border width (edge of monitor to active area)
Top/Left/Right 5.4 mm 6.0 mm
Bottom 20.7 mm 21.3 mm
Adjustability
Height adjustable
stand
NA
Tilt -5° to 21°
12 | About your monitor
Swivel NA
Pivot NA
Cable management Yes
Dell Display Manager
(DDM)Compatibility
Easy Arrange and other key features
Security Security lock slot (cable lock sold separately)
* At panel native resolution only, under Custom Mode preset.
Resolution specifications
Model S2421HN/S2421NX/S2721HN/S2721NX
Horizontal scan range 30 kHz to 83 kHz
Vertical scan range 48 Hz to 75 Hz
Maximum preset
resolution
1920 x 1080 at 60 Hz
Video display capabilities
(HDMI playback)
480i, 480p, 576i, 576p, 720p, 1080i, 1080p
About your monitor | 13
Preset display modes
S2421HN/S2421NX/S2721HN/S2721NX
Display Mode Horizontal
Frequency
(kHz)
Vertical
Frequency
(Hz)
Pixel Clock
(MHz)
Sync Polarity
(Horizontal/
Vertical)
VGA, 720 x 400 31.5 70.0 28.3 -/+
VGA, 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 60.0 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 +/+
MAC, 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 900 60.0 60.0 108.0 +/+
CVT, 1920 x 1080
67.5
60.0
148.5
+/+
CVT, 1920 x 1080 83.89 75.0 174.5 +/-
Electrical specifications
Model S2421HN/S2421NX/S2721HN/S2721NX
Video input signals •Digital video signal for each dierential line
Per dierential line at 100 ohm impedance
•HDMI signal input support
Input voltage/ frequency/
current
100-240 VAC / 50 or 60 Hz ± 3 Hz / 1.5 A
(maximum)
Inrush current 120 V: 30 A (maximum)
240 V: 60 A (maximum)
14 | About your monitor
Physical characteristics
Model S2421HN/S2421NX S2721HN/S2721NX
Connector type •2 x HDMI1.4 ports
•1 x Audio line-out port
Signal cable type 1.8 m HDMI1.4 cable
Dimensions (with stand)
Height 412.8 mm (16.25 in.) 453.3 mm (17.85 in.)
Width 537.8 mm (21.17 in.) 609.9 mm (24.01 in.)
Depth 152.8 mm (6.02 in.) 186.8 mm (7.35 in.)
Dimensions (without stand)
Height 322.6 mm (12.70 in.) 363.6 mm (14.32 in.)
Width 537.8 mm (21.17 in.) 609.9 mm (24.01 in.)
Depth 53.8 mm (2.12 in.) 54.0 mm (2.13 in.)
Stand dimensions
Height 171.6 mm (6.76 in.) 176.0 mm (6.93 in.)
Width 249.0 mm (9.80 in.) 257.2 mm (10.13 in.)
Depth 152.8 mm (6.02 in.) 186.8 mm (7.35 in.)
Weight
Weight with packaging 5.9 kg (13.00 lb.) 7.6 kg (16.76 lb.)
Weight with stand assembly and
cables
4.1 kg (9.04 lb.) 5.2 kg (11.46 lb)
Weight without stand assembly
(For wall mount or VESA mount
considerations - no cables)
3.3 kg (7.28 lb.) 4.3 kg (9.48 lb.)
Weight of stand assembly 0.5 kg (1.19 lb.) 0.7 kg (1.54 lb.)
About your monitor | 15
Environmental characteristics
Model S2421HN/S2421NX/S2721HN/S2721NX
Compliant Standards
•ENERGY STAR certified Monitor.
•TCO Certified Display.
•RoHS Compliant.
•BFR/PVC Reduce monitor (excluding external cables).
•Arsenic-Free glass and Mercury-Free for the panel only.
Temperature
Operating 0°C to 40°C (32°F to 104°F)
Non-operating –20°C to 60°C (–4°F to 140°F)
Humidity
Operating 10% to 80% (non-condensing)
Non-operating 5% to 90% (non-condensing)
Altitude
Operating (maximum) 5,000 m (16,404 ft.)
Non-operating (maximum) 12,192 m (40,000 ft.)
Thermal dissipation
S2421HN/S2421NX 71.65 BTU/hour (maximum)
54.59 BTU/hour (typical)
S2721HN/S2721NX 98.95 BTU/hour (maximum)
64.83 BTU/hour (typical)
16 | About your monitor
Power management modes
If you have VESA’s DPM-compliant video card or software installed in your PC, the
monitor can automatically reduce its power consumption when not in use. This is
referred to as standby mode*. If the computer detects input from the keyboard,
mouse, or other input devices, the monitor automatically resumes functioning. The
following table shows the power consumption and signaling of this automatic power
saving feature.
S2421HN/S2421NX
VESA
Modes
Horizontal
Sync
Vertical
Sync
Video Power
Indicator
Power
Consumption
Normal
operation
Active Active Active White 21 W (maximum)**
16 W (typical)
Active-off
mode
Inactive Inactive Off White
(Glowing)
Less than 0.3 W
Switch off - - - Off Less than 0.3 W
Power Consumption Pon 11.74 W
Total Energy Consumption (TEC) 37.3 kWh
S2721HN/S2721NX
VESA
Modes
Horizontal
Sync
Vertical
Sync
Video Power
Indicator
Power
Consumption
Normal
operation
Active Active Active White 29 W (maximum)**
19 W (typical)
Active-off
mode
Inactive Inactive Off White
(Glowing)
Less than 0.3 W
Switch off - - - Off Less than 0.3 W
Power Consumption Pon 13.82 W
Total Energy Consumption (TEC) 43.68 kWh
About your monitor | 17
The OSD operates only in the normal operation mode. If you press any button in the
active-off mode, the following message is displayed:
No HDMI1 signal from your device.
Dell 24 Monitor
Press any key on the keyboard or move the mouse to wake it up.
If there is no display, press the monitor button again to select
the correct input source.
S2421HN/S2421NX
or
No HDMI1 signal from your device.
Dell 27 Monitor
Press any key on the keyboard or move the mouse to wake it up.
If there is no display, press the monitor button again to select
the correct input source.
S2721HN/S2721NX
*Zero power consumption in OFF mode can only be achieved by disconnecting the AC
mains cable from the monitor.
**Maximum power consumption with maximum luminance.
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.
Activate the computer and the monitor to gain access to the OSD.
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.
18 | About your monitor
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.
Pin Assignments
HDMI port
Pin number 19-pin side of theconnected signal cable
1TMDS DATA 2+
2TMDS DATA 2 SHIELD
3TMDS DATA 2-
4TMDS DATA 1+
5TMDS DATA 1 SHIELD
6TMDS DATA 1-
7TMDS DATA 0+
8TMDS DATA 0 SHIELD
9TMDS DATA 0-
10 TMDS CLOCK+
11 TMDS CLOCK SHIELD
12 TMDS CLOCK-
13 CEC
14 Reserved (N.C. on device)
15 DDC CLOCK (SCL)
16 DDC DATA (SDA)
17 DDC/CEC Ground
18 +5 V POWER
19 HOT PLUG DETECT
About your monitor | 19
Plug-and-play
You can install the monitor in any Plug-and-Play-compatible system. The monitor
automatically provides the computer system with its extended display identification
data (EDID) using display data channel (DDC) protocols so the computer can configure
itself and optimize the monitor settings. Most monitor installations are automatic;
you can select different settings if desired. For more information about changing the
monitor settings, see Operating the monitor.
LCD monitor quality and pixel policy
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 LCD Monitor Pixel Policy, see
Dell support site at: https://www.dell.com/pixelguidelines.
Ergonomics
CAUTION: Improper or prolonged usage of keyboard may result in injury.
CAUTION: Viewing the monitor screen for extended periods of time may
result in eye strain.
For comfort and efficiency, observe the following guidelines when setting up and using
your computer workstation:
• Position your computer so that the monitor and keyboard are directly in front of
you as you work. Special shelves are commercially available to help you correctly
position your keyboard.
• To reduce the risk of eye strain and neck/arm/back/shoulder pain from using the
monitor for long periods of time, we suggest you to:
1. Set the distance of the screen between 20 to 28 in. (50-70 cm) from your
eyes.
2. Blink frequently to moisten your eyes or wet your eyes with water after
prolonged usage of the monitor.
3. Take regular and frequent breaks for 20 minutes every two hours.
4. Look away from your monitor and gaze at a distant object at 20 feet away for
at least 20 seconds during the breaks.
5. Perform stretches to relieve tension in the neck, arm, back, and shoulders
during the breaks.
• Make sure that the monitor screen is at eye level or slightly lower when you are
sitting in front of the monitor.
• Adjust the tilt of the monitor, its contrast, and brightness settings.
20 | About your monitor
• 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.
• Use a chair that provides good lower-back support.
• Keep your forearms horizontal with your wrists in a neutral, comfortable position
while using the keyboard or mouse.
• Always leave space to rest your hands while using the keyboard or mouse.
• Let your upper arms rest naturally on both sides.
• Ensure that your feet are resting flat on the floor.
• When sitting, make sure that the weight of your legs is on your feet and not
on the front portion of your seat. Adjust your chair’s height or use a footrest if
necessary to maintain a proper posture.
• Vary your work activities. Try to organize your work so that you do not have to sit
and work for extended periods of time. Try to stand or get up and walk around at
regular intervals.
• Keep the area under your desk clear of obstructions and cables or power cords
that may interfere with comfortable seating or present a potential trip hazard.
monitor screen at or
below eye level
monitor and
keyboard
positioned
directly in front
of the user
feet at on the
oor
wrists relaxed
and at
About your monitor | 21
Handling and moving your display
To ensure the monitor is handled safely when lifting or moving it, follow the guidelines
mentioned below:
• Before moving or lifting the monitor, turn off your computer and the monitor.
• Disconnect all cables from the monitor.
• Place the monitor in the original box with the original packing materials.
• Hold the bottom edge and the side of the monitor firmly without applying
excessive pressure when lifting or moving the monitor.
• When lifting or moving the monitor, ensure the screen is facing away from you
and do not press on the display area to avoid any scratches or damage.
• When transporting the monitor, avoid any sudden shock or vibration to it.
22 | About your monitor
• When lifting or moving the monitor, do not turn the monitor upside down while
holding the stand base or stand riser. This may result in accidental damage to the
monitor or cause personal injury.
Maintenance guidelines
Cleaning your monitor
CAUTION: Read and follow the Safety instructions before cleaning the
monitor.
WARNING: Before cleaning the monitor, unplug the monitor power cable
from the electrical outlet.
For best practices, follow the instructions in the list below when unpacking, cleaning,
or handling your monitor:
• To clean your anti-static screen, lightly dampen a soft, clean cloth with water. If
possible, use a special screen-cleaning tissue or solution suitable for the anti-
static coating. Do not use benzene, thinner, ammonia, abrasive cleaners, or
compressed air.
• Use a lightly-dampened, warm cloth to clean the monitor. Avoid using detergent
of any kind as some detergents leave a milky film on the monitor.
• If you notice white powder when you unpack your monitor, wipe it off with a
cloth.
• Handle your monitor with care as a darker-colored monitor may get scratched
and show white scuff marks more than a lighter-colored monitor.
• To help maintain the best image quality on your monitor, use a dynamically
changing screen saver and turn off your monitor when not in use.
Setting up the monitor | 23
Setting up the monitor
Connecting the stand
NOTE: The stand riser and stand base are detached when the monitor is
shipped from the factory.
NOTE: The following instructions are applicable only for the stand that
was shipped with your monitor. If you are connecting a stand that you
purchased from any other source, follow the set up instructions that were
included with the stand.
CAUTION: Place monitor of a flat, clean, and soft surface to avoid
scratching the display panel.
To attach the monitor stand:
1. Align the tabs on the stand base with the slots on the stand riser.
2. Insert the stand riser on the stand base firmly.
3. Open the screw handle at the bottom of the stand base, and rotate it clockwise
to tighten the screw firmly. Then close the screw handle.
3
2
1
24 | Setting up the monitor
4. Open the monitor protective cover and install the VESA screw cover.
5. Align the tabs on the stand-riser bracket with the grooves at the back of the
monitor.
6. Insert the stand-riser bracket into monitor groove until it snaps into place.
5
6
Setting up the monitor | 25
CAUTION: Hold the stand riser firmly when lifting the monitor to avoid any
accidental damage.
7. Hold the stand riser and lift the monitor carefully, then place it on a at surface.
8. Lift the protective cover from the monitor.
26 | Setting up the monitor
Using the tilt
NOTE: The following instructions are applicable only for the stand that
was shipped with your monitor. If you are connecting a stand that you
purchased from any other source, follow the set up instructions that were
included with the stand.
With the stand attached to the monitor, you can tilt the monitor for the most
comfortable viewing angle.
5°
21°
NOTE: The stand is detached when the monitor is shipped from the
factory.
Setting up the monitor | 27
Connecting your monitor
WARNING: Before you begin any of the procedures in this section, follow
the Safety instructions.
To connect your monitor to the computer:
1. Turn o your computer.
2. Connect the HDMI cable from your monitor to thecomputer.
3. Turn on your monitor.
4. Select the correct input source from the OSD Menu on your monitor and then
turn on your computer.
Connecting the HDMI cable
HDMI
HDMI
28 | Setting up the monitor
Organizing your cables
HDMI
After connecting all necessary cables to your monitor and computer, (see Connecting
your monitor for cable attachment) organize all cables as shown above.
Securing your monitor using Kensington lock (optional)
The security lock slot is located at the bottom of the monitor. (See Security lock slot)
For more information on using the Kensington lock (purchased separately), see the
documentation that is shipped with the lock.
Secure your monitor to a table using the Kensington security lock.
NOTE: The image is for the purpose of illustration only. Appearance of the
lock may vary.
Setting up the monitor | 29
Removing the monitor stand
CAUTION: To prevent scratches on the LCD screen while removing the
stand,make sure that the monitor is placed on a soft, clean surface.
NOTE: The following instructions are applicable only for the stand that
was shipped with your monitor. If you are connecting a stand that you
purchased from any other source, follow the set up instructions that were
included with the stand.
To remove the stand:
1. Place a at cushion or a sitting mat near the edge of a table and place the
monitor on it with the display facing down.
2. Press the stand down to access to the release latch.
3. Use a long screwdriver to press the release latch.
4. While pressing the release latch, slide out the stand assembly from the monitor.
4
3
To remove the VESA cover:
Press the dimple on the VESA cover to release it from the back of the display.
30 | Setting up the monitor
Wall mounting (Optional)
DELL S2421HN
Flat Panel Monitor / Monitor Plano Panel / Moniteur à écran plat / 液晶顯示器
Model No. / N° de Modelo / Numéro de m odèle /型號: S 2421Ht
Input Rating / Entrada / Daya Tegangan / Tension d’entrée: 100-240V ~ 50/60Hz 1.5A
輸入電源:交流電壓 100-240伏特, 1.5 安培, 50/60赫茲
Удельная мощность рабочего режима -X,XXX Вт/см2
Потребляемая мощность изделием в режиме ожидания -X,XX Вт
Потребляемая мощность изделием в выключенном режиме - X,XX Вт
Made in China / Fabricado en China / Fabriqué en Chine / Сделано в Китае / 製造地:中國
警語:使用過度恐傷害視力
신청인: Wistron Corporation (For Korea)
Wistron InfoComm (Zhongshan) Corporation Linhai Branch
제조자: Wistron InfoComm (Zhongshan) Corporation Linhai Branch
A/S 연락처: 080-854-0066
제조국: 중국
CAN ICES-3 (B)/NMB-3(B)
Apparatet må tilkoples jordet stikkontakt.
Apparaten skall anslutas till jordat uttag.
Apparatets stikprop skal tilsluttes en stikkontakt med jord,
som giver forbindelse til stikproppens jord.
Laite on liitettävä suojakoskettimilla varustettuun pistorasiaan.
Consumo de energía en operación: XX.XX Wh
XXXXX
Address for EU Only:
Raheen Business Park
Limerick Ireland
www.dell.com/regulatory_compliance
XXXXXXXX-XXXXX
R-R-WT1-S2421Ht
И005-20
This device complies with part 15 of the FCC Rules.
Operation is subject to the following two conditions:
(1) this device may not cause harmful interference, and
(2) this device must accept any interference received,
including interference that may cause undesired operation.
XXXXXX-XX
IS 13252 (Part 1)/
IEC 60950-1
R-41071650
www.bis.gov.in
For UK only: Cain Road, Bracknell, RG12 1LF
ID XXXXXXXXXX
ID
XXXXXXXXXX
DELL S2421HN
Flat Panel Monitor / 液晶显示器
型号 : S2421HN
Input Rating / 输入电源 :
100-240V ~ 50/60Hz 1.5A
Made in China / 制造地:中国
Manufactured date / 制造日期:
E
t
NOTE: Use M4 x 10 mm screws to secure the wall-mounting kit to the
monitor.
See the documentation that is shipped with the VESA-compatible wall mounting kit.
1. Place a at cushion or a sitting mat near the edge of a table and place the
monitor on it with the display facing down.
2. Remove the stand.
3. Using a Phillips crosshead screwdriver, remove the four screws that secure the
back panel.
4. Connect the mounting bracket from the wall mounting kit to the monitor.
5. Follow the instructions that shipped with the wall-mounting kit and mount the
monitor on the wall.
NOTE: For use only with UL or CSA or GS-listed wall mount bracket
with minimum weight/load bearing capacity of 13.2 kg (S2421HN/
S2421NX)/17.2 kg (S2721HN/S2721NX).
Operating the monitor | 31
Operating the monitor
Power on the monitor
Press the button to turn on the monitor.
Using the front panel controls
Use the control buttons at the bottom edge of the monitor to adjust the specifications
of the image being displayed. When using the control buttons, an On-Screen Display
(OSD) menu appears on the screen with numeric values.
3 4 51 2
32 | Operating the monitor
The following table describes the front panel buttons:
Front-Panel Button Description
1
Shortcut key:
Preset Modes
Use this button to choose from a list of preset
colormodes.
2
Shortcut key:
Input Source
Use this button to choose from a list of input
sources.
3
Menu
Use this menu button to launch the on-screen
display (OSD) and select the OSD menu.
See Accessing the menu system.
4
Exit
Use this button to go back to the main menu or exit
the OSD main menu.
5
Power(with power light
indicator)
Use the Power button to turn the monitor On and
Off.
The white LED indicates the monitor is On and fully
functional.
A breathing white LED indicates DPMS Standby
Mode.
Operating the monitor | 33
Using the OSD lock function
You can lock the front-panel control buttons to prevent access to the OSD menu and/
or power button.
Use the Lock menu to lock the button(s).
1. Select one of the following options.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast
Power Button
Language
Transparency
Timer
Menu + Power Buttons
Disable
Lock
Reset Menu
Menu Buttons
2. The following message appears.
Dell 24/27 Monitor
Are you sure you want to lock the Menu Buttons?
To unlock the Buttons, refer to the User’s Guide.
Yes No
S2421HN/S2421NX/S2721HN/S2721NX
3. Select Yes to lock the buttons. Once locked, pressing any control button will
display the lock icon
Use the front-panel control button to lock the button(s).
3 4 51 2
34 | Operating the monitor
1. Press and hold Button 4 for four seconds, a menu appears on the screen.
Dell 24/27 Monitor
Select Option:
2. Select one of the following options:
Options Description
1
Menu Button lock
Select this option to lock OSD menu function.
2
Power Button lock
Use this option to lock power button. This will
prevent the user to turn off the monitor using the
power button.
3
Menu and Power Button
lock
Use this option to lock OSD menu and power
button to turn off the monitor.
4
Built-in Diagnostics
Use this option to run the built-in diagnostics, see
Built-in Diagnostics.
To unlock the button(s).
Press and hold Button 4 for foru seconds until a menu appears on the screen. The
following table describes the options to unlock the front-panel control buttons.
Dell 24/27 Monitor
Select Option:
Dell 24/27 Monitor
Select Option:
Dell 24/27 Monitor
Select Option:
Operating the monitor | 35
Options Description
1
Menu Button unlock
Use this option to unlock OSD menu function.
2
Power Button unlock
Use this option to unlock power button to turn off
the monitor.
3
Menu and Power Button
unlock
Use this option to unlock OSD menu and power
button to turn off the monitor.
4
Built-in Diagnostics
Use this option to run the built-in diagnostics, see
Built-in Diagnostics.
Front-panel button
Use the buttons on the front of the monitor to adjust the image settings.
2 31
Front Panel Button Description
1
Up Down
Use the Up (increase) and Down (decrease) buttons to
adjust items in the OSD menu.
2
OK
Use the OK button to confirm your selection.
36 | Operating the monitor
3
Back
Use the Back button to go back to the previous menu.
Using the On-Screen Display (OSD) menu
Accessing the menu system
NOTE: The changes you make using the OSD menu are automatically saved
when youmove to another OSD menu, when you exit the OSD menu, or
when the OSD menu todisappears automatically.
1. Press the button to launch the OSD menu and display the main menu.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast
75%
75%
2. Press the and buttons to move between options. As you move from one
icon to another, the option name is highlighted.
3. Press the or or button once to activate the highlighted option.
4. Press the and buttons to select the desired parameter.
5. Press to enter the slide bar and then use the or button, according to
the indicators on the menu, to make your changes.
6. Select the to return to previous menu or to accept and return to previous
menu.
Operating the monitor | 37
Icon Menu and
Submenus
Description
Brightness/
Contrast
Use this menu to activate Brightness/Contrast adjustment.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast
75%
75%
Brightness Brightness adjusts the luminance of the backlight
(minimum 0; maximum 100).
Press the button to increase brightness.
Press the button to decrease brightness.
Contrast Adjust the Brightness first, and then adjust Contrast only if
further adjustment is necessary.
Press the button to increase contrast and press the
button to decrease contrast (between 0 and 100).
Contrast adjusts the difference between darkness and
lightness on the monitor.
Input Source Use the Input Source menu to select between different
video inputs that are connected to your monitor.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast HDMI1
HDMI2
Reset Input Source
On
Auto select
38 | Operating the monitor
Icon Menu and
Submenus
Description
HDMI 1 Select HDMI1 input when you are using the HDMI1
connector.
Use to select the HDMI input source.
HDMI 2 Select HDMI2 input when you are using the HDMI2
connector.
Use to select the HDMI input source.
Auto Select Use to select Auto Select, the monitor scans for
available input sources.
Reset Input
Source
Resets your monitor’s Input Source settings to the factory
defaults.
Color Use the Color menu to adjust the color setting mode.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast Preset Modes Standard
Input Color Format RGB
Reset Color
Operating the monitor | 39
Icon Menu and
Submenus
Description
Preset Modes When you select Preset Modes, you can choose Standard,
ComfortView, Movie, FPS, RTS, RPG, Warm, Cool or
Custom Color from the list.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast Preset Modes
Input Color Format
Reset Color
ComfortView
Movie
FPS
RTS
RPG
Standard
Warm
Cool
Custom Color
•Standard: Default color settings. This is the default preset
mode.
•ComfortView: Decreases the level of blue light emitted
from the screen to make viewing more comfortable for your
eyes.
WARNING: The possible long-term effects of blue light
emission from the monitor may cause personal injury
such as digital eye strain, eye fatigue and damage to
the eyes. Using monitor for extended periods of time
may also cause pain in parts of body such as neck,
arm, back and shoulder. For more information, see
Ergonomics.
•Movie: Loads color settings ideal for movies.
•FPS : Loads color settings ideal for First-Person Shooter
games.
•RTS : Loads color settings ideal for Real-Time Strategy
games.
•RPG : Loads color settings ideal for Role-Playing games.
40 | Operating the monitor
Icon Menu and
Submenus
Description
•Warm: Increases the color temperature. The screen
appears warmer with a red/yellow tint.
•Cool : Decreases the color temperature. The screen
appears cooler with blue tint.
•Custom Color: Allows you to manually adjust the color
settings. Press the and buttons to adjust the Red,
Green, and Blue values and create your own preset color
mode.
Input Color
Format
Allows you to set the video input mode to:
•RGB: Select this option if your monitor is connected to a
computer (or DVD player) using the HDMI cable.
•YPbPr: Select this option if your DVD player supports only
YPbPr output.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast Preset Modes
Input Color Format
Reset Color YPbPr
RGB
Hue Use or to adjust the hue from 0 to 100.
NOTE: Hue adjustment is available only for Movie and FPS,
RTS, RPG mode.
Saturation Use or to adjust the saturation from 0 to 100.
NOTE: Saturation adjustment is available only for Movie and
FPS, RTS, RPG mode.
Reset Color Resets your monitor’s color settings to the factory defaults.
Operating the monitor | 41
Icon Menu and
Submenus
Description
Display Use the Display menu to adjust image.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast
Response Time
Sharpness
Reset Display
50
Normal
Wide 16:9
Aspect Ratio
Aspect Ratio Select the image ratio between 16:9 (wide), 4:3, and 5:4.
Sharpness Makes the image look sharper or softer.
Use or to adjust the sharpness from ‘0’ to ‘100’.
Response
Time
Allows you to set the Response Time to Normal, Fast or
Extreme.
Reset Display Restores the display settings to factory defaults.
42 | Operating the monitor
Icon Menu and
Submenus
Description
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.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast EnglishLanguage
Transparency
Timer
Lock
20
20 s
Disable
Reset Menu
Language Set the OSD display to one of eight languages.
(English, Spanish, French, German, Brazilian Portuguese,
Russian, Simplified Chinese, or Japanese).
Transparency Select this option to change the menu transparency by using
and (min. 0 / max. 100).
Timer OSD Hold Time: Sets the length of time the OSD remains
active after you press a button.
Use the and buttons to adjust the slider in 1-second
increments, from 5 to 60 seconds.
Operating the monitor | 43
Icon Menu and
Submenus
Description
Lock Controls user access to adjustments. The buttons are locked.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast Language
Transparency
Timer
Lock
Reset Menu Power Button
Menu + Power Buttons
Menu Buttons
Disable
•Menu Buttons: Through OSD to lock the Menu buttons.
•Power Button: Through OSD to lock the Power button.
•Menu + Power Buttons: Through OSD to lock the all of
Menu and Power buttons.
•Disable: Press and hold the button next to the power
button for four seconds to unlock the buttons.
Reset Menu Restore the menu settings to factory defaults.
44 | Operating the monitor
Icon Menu and
Submenus
Description
Personalize
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast
Input SourceShortcut Key 2
On In On ModePower Button LED
Reset Personalization
Preset Modes
Shortcut Key 1
Shortcut
key 1
Select from Preset Modes, Brightness/Contrast, Input
Source, Aspect Ratio set as shortcut key 1.
Shortcut
key 2
Select from Preset Modes, Brightness/Contrast, Input
Source, Aspect Ratio set as shortcut key 2.
Power Button
LED
Allows you to set the state of the power light to save energy.
Reset
Persona-
lization
Restores shortcut keys to factory defaults.
Operating the monitor | 45
Icon Menu and
Submenus
Description
Others Select this option to adjust the OSD settings suchas the
DDC/CI, LCD conditioning, and so on.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast
00X000
O
ABCDEF
On
LCD Conditioning
DDC/CI
Firmware
Service Tag
Factory Reset ENERGY STAR
Display Info
Reset Others
Display Info Displays the monitor’s current settings.
DDC/CI DDC/CI (Display Data Channel/Command Interface) allows
you to adjust the monitor settings using software on your
computer.
Select Off to turn off this feature.
Enable this feature for best user experience and optimum
performance of your monitor.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast
O
On
LCD Conditioning
DDC/CI
Firmware
Reset Others
Factory Reset
Display Info
Service Tag
46 | Operating the monitor
Icon Menu and
Submenus
Description
LCD
Conditioning
Helps reduce minor cases of image retention. Depending on
the degree of image retention, the program may take some
time to run. Select On to start the process.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast
LCD Conditioning
DDC/CI
Firmware
Reset Others
On
Factory Reset
Display Info
O
Service Tag
Firmware Displays the firmware version of your monitor.
Service Tag Displays the Service Tag. The Service Tag is a unique
alphanumeric identifier that allows Dell to identify the product
specifications and access warranty information.
NOTE: The Service Tag is also printed on a label located at
the back of the cover.
Reset Others Restores other settings, such as DDC/CI, to factorydefaults.
Factory
Reset
Restores all preset values to the factory default settings.
These are also the settings for ENERGY STAR® tests.
Dell 24/27 Monitor
Input Source
Color
Personalize
Display
Menu
Others
Brightness/Contrast
00X000
O
ABCDEF
On
LCD Conditioning
DDC/CI
Firmware
Service Tag
ENERGY STAR
Display Info
Reset Others
Factory Reset
Operating the monitor | 47
OSD warning messages
When the monitor does not support a particular resolution mode, you can see the
following message:
S2421HN/S2421NX S2721HN/S2721NX
The current input timing is not supported by the monitor display. Please
change your input timing to
listed timing as per the monitor specifications.
1920x1080, 60Hz or any other monitor
S2421HN/S2421NX
Dell 24 Monitor
The current input timing is not supported by the monitor display. Please
change your input timing to
listed timing as per the monitor specifications.
1920x1080, 60Hz or any other monitor
S2721HN/S2721NX
Dell 27 Monitor
This means that the monitor cannot synchronize with the signal that it is receiving
from the computer. See Resolution specifications for the Horizontal and Vertical
frequency ranges addressable by this monitor. Recommended mode is 1920 x 1080.
You can see the following message before the DDC/CI function is disabled:
S2421HN/S2421NX S2721HN/S2721NX
Dell 24 Monitor
The function of adjusting display setting using PC application will be
disabled.
Do you wish to disable DDC/CI function?
Yes No
S2421HN/S2421NX
Dell 27 Monitor
The function of adjusting display setting using PC application will be
disabled.
Do you wish to disable DDC/CI function?
Yes No
S2721HN/S2721NX
When the monitor enters the Standby mode, the following message will appears:
S2421HN/S2421NX S2721HN/S2721NX
Dell 24 Monitor
Going into Standby Mode...
S2421HN/S2421NX
Dell 27 Monitor
Going into Standby Mode...
S2721HN/S2721NX
Activate the computer and wake up the monitor to gain access to the OSD.
48 | Operating the monitor
If you press any button other than the power button, the following messages will
appear depending on the selected input:
S2421HN/S2421NX S2721HN/S2721NX
No HDMI1 signal from your device.
Dell 24 Monitor
Press any key on the keyboard or move the mouse to wake it up.
If there is no display, press the monitor button again to select
the correct input source.
S2421HN/S2421NX
No HDMI1 signal from your device.
Dell 27 Monitor
Press any key on the keyboard or move the mouse to wake it up.
If there is no display, press the monitor button again to select
the correct input source.
S2721HN/S2721NX
If either HDMI1, HDMI2 input is selected and the corresponding cable is not connected,
a floating dialog box as shown below appears.
S2421HN/S2421NX S2721HN/S2721NX
The display will go into Standby Mode in 4 minutes.
www.dell.com/support/S2421HN
www.dell.com/support/S2421NX
Dell 24 Monitor
S2421HN/S2421NX
No HDMI1 Cable
or
The display will go into Standby Mode in 4 minutes.
www.dell.com/support/S2421HN
www.dell.com/support/S2421NX
Dell 24 Monitor
S2421HN/S2421NX
No HDMI2 Cable
The display will go into Standby Mode in 4 minutes.
www.dell.com/support/S2721HN
www.dell.com/support/S2721NX
Dell 27 Monitor
S2721HN/S2721NX
No HDMI1 Cable
or
The display will go into Power Save Mode in 4 minutes.
www.dell.com/support/S2721HN
www.dell.com/support/S2721NX
Dell 27 Monitor
S2721HN/S2721NX
No HDMI2 Cable
See Troubleshooting for more information.
Operating the monitor | 49
Setting the maximum resolution
To set the maximum resolution for the monitor:
In Windows 7, Windows 8 or Windows 8.1:
1. For Windows 8 or Windows 8.1 only, select the Desktop tile to switch to classic
desktop. For Windows Vista and Windows 7, skip this step.
2. Right-click on the desktop and click Screen Resolution.
3. Click the Dropdown list of the Screen Resolution and select 1920 x 1080.
4. Click OK.
In Windows 10:
1. Right-click on the desktop and click Display Settings.
2. Click Advanced display settings.
3. Click the dropdown list of Resolution and select 1920 x 1080.
4. Click Apply.
If you do not see 1920 x 1080 as an option, you may need to update your graphics
driver. Depending on your computer, complete one of the following procedures:
If you have a Dell desktop or portable computer:
• 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):
• Go to your computer manufacturer’s support website and download the latest
graphic drivers.
• Go to your graphics card manufacturer’s website and download the latest graphic
drivers.
50 | Troubleshooting
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. Turn o both your computer and the monitor.
2. Unplug the video cable from the back of the computer. To ensure proper Self-Test
operation, remove all video cables from the back of computer.
3. Turn on the monitor.
The floating dialog box should appear on-screen (against a black background), if the
monitor cannot sense a video signal and is working correctly. While in self-test mode,
the power LED remains white. Also, depending upon the selected input, one of the
dialogs shown below will continuously scroll through the screen.
S2421HN/S2421NX S2721HN/S2721NX
The display will go into Standby Mode in 4 minutes.
www.dell.com/support/S2421HN
www.dell.com/support/S2421NX
Dell 24 Monitor
S2421HN/S2421NX
No HDMI1 Cable
or
The display will go into Standby Mode in 4 minutes.
www.dell.com/support/S2421HN
www.dell.com/support/S2421NX
Dell 24 Monitor
S2421HN/S2421NX
No HDMI2 Cable
The display will go into Standby Mode in 4 minutes.
www.dell.com/support/S2721HN
www.dell.com/support/S2721NX
Dell 27 Monitor
S2721HN/S2721NX
No HDMI1 Cable
or
The display will go into Power Save Mode in 4 minutes.
www.dell.com/support/S2721HN
www.dell.com/support/S2721NX
Dell 27 Monitor
S2721HN/S2721NX
No HDMI2 Cable
4. This box also appears during normal system operation if the video cable is
disconnected or damaged.
5. Turn o your monitor and reconnect the video cable; then turn on both your
computer and the monitor.
Troubleshooting | 51
If your monitor screen remains blank after you use the previous procedure, check your
video controller and computer, because your monitor is functioning properly.
Built-in diagnostics
Your monitor has a built-in diagnostic tool that helps you determine if the screen
abnormality you are experiencing is an inherent problem with your monitor, or with your
computer and video card.
3 4 51 2
To run the built-in diagnostics:
1. Ensure that the screen is clean (no dust particles on the surface of the screen).
2. Press and hold Button 4 for four seconds, a menu appears on the screen.
3. Select the built-in diagnostics option. A gray screen appears.
4. Carefully inspect the screen for abnormalities.
5. Press Button 1 on the front panel again. The color of the screen changes to red.
6. Inspect the display for any abnormalities.
7. Repeat steps 5 to 6 to inspect the display when it changes to green, blue, black,
white, and text screens.
The test is complete when the text screen appears. To exit, press Button 1 again.
If you do not detect any screen abnormalities during the built-in diagnostic tool, the
monitor is functioning properly. Check the video card and computer.
52 | Troubleshooting
Common problems
The following table contains general information about common monitor problems you
might encounter and the possible solutions:
Common
symptoms
What you
experience
Possible solutions
No Video/
Power LED off
No picture •Ensure that the video cable connecting the
monitor and the computer is properly connected
and secure.
•Verify that the power outlet is functioning
properly using any other electrical equipment.
•Ensure that the power button is depressed fully.
•Ensure that the correct input source is selected
in the Input Source menu.
No Video/
Power LED on
No picture or no
brightness
•Increase brightness and contrast controls
through OSD.
•Perform monitor self-test feature check.
•Check for bent or broken pins in the video cable
connector.
•Run the built-in diagnostics.
•Ensure that the correct input source is selected
in the Input Source menu.
Missing Pixels LCD screen has
spots
•Cyclepoweron-off.
•Pixelthatispermanentlyoffisanaturaldefect
that can occur in LCD technology.
•FormoreinformationonDellMonitorQuality
and Pixel Policy, see Dell Support site at:
www.dell.com/support/monitors.
Stuck-on Pixels LCD screen has
bright spots
•CyclepowerOn-Off.
•Pixelthatispermanentlyoffisanaturaldefect
that can occur in LCD technology.
•FormoreinformationonDellMonitorQuality
and PixelPolicy, see Dell Support site at:
www.dell.com/support/monitors.
Brightness
Problems
Picture too dim
or too bright
•Reset the monitor to factory settings.
•Adjust brightness and contrast controls through
OSD.
Troubleshooting | 53
Common
symptoms
What you
experience
Possible solutions
Safety Related
Issues
Visible signs of
smoke or sparks
•Do not perform any troubleshooting steps.
•Contact Dell immediately.
Intermittent
Problems
Monitor
malfunctions on
& off
•Ensure that the video cable connecting the
monitor to the computer is connected properly
and is secure.
• Reset the monitor to factory settings.
•Perform monitor self-test feature check to
determine if the intermittent problem occurs in
self-test mode.
Missing Color Picture missing
color
•Perform monitor self-test.
•Ensure 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
not good
•Change the settings of the Preset Modes
in the Color menu OSD depending on the
application.
•Adjust R/G/B value under Custom Color in
Color menu OSD.
•Change the Input Color Format to PC RGB or
YPbPr in the Color menu OSD.
•Run the built-in diagnostics.
Image retention
from a static
image left on
the monitor for
a long period of
time
Faint shadow
from the static
image displayed
appears on the
screen
•Use the Power Management feature to turn
off the monitor at all times when not in use
(for more information, see Power management
modes).
•Alternatively, use a dynamically changing
screensaver.
54 | Troubleshooting
Product specific problems
Problem What you
experience
Possible solutions
Screen image is
too small
Image is centered
on screen, but does
not fill entire viewing
area
•Check the Aspect Ratio setting in the
Display menu OSD.
•Reset the monitor to factory settings.
Cannot adjust
the monitor
with the
buttons on the
front panel
OSD does not
appear on the
screen
•Turn off the monitor, unplug the monitor
power cable, plug it back, and then turn on
the monitor.
No Input Signal
when user
controls are
pressed
No picture, the LED
light is white
•Check the signal source. Ensure the
computer is not in the power saving mode
by moving the mouse or pressing any key on
the keyboard.
•Check whether the signal cable is plugged
in properly. Connect the signal cable again, if
necessary.
•Reset the computer or video player.
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, the monitor may display in full
screen.
•Run the built-in diagnostics.
Appendix | 55
Appendix
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.
Contacting Dell
For customers in the United States, call 800-WWW-DELL (800-999-3355).
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.
Dell provides several online and telephone-based support and service options.
Availability varies by country and product, and some services may not be
available in your area.
• Online technical assistance — www.dell.com/support/monitors
• Contacting Dell — www.dell.com/contactdell
Outline dimension
15.0
[0.59]
53.8
[2.12]
150.7
[5.93]
5
21
249.0
[9.80]
28.2
[1.11]
407.4
[16.04]
165.4
[6.51]
88.8
[3.50]
409.9
[16.14]
1.8
[0.07]
14.2
[0.56]
527.0
[20.75]
537.8
[21.17]
296.5
[11.67]
322.6
[12.70]
5.4
[0.21]
20.7
[0.82]
5.4
[0.21]
5.4
[0.21]
111.0
[4.37] 412.8
[16.25]
14.0
[0.55]
9.0
[0.36]
44.7
[1.76]
159.4
[6.28]
171.6
[6.76]
152.8
[6.02]
79.9
[3.15]
100.0(2x)
[3.94]
122.0 (2x)
[4.80]
Unit : mm(inch)
Dimension : Nominal
Drawing : Not to scale
S2421H/HN/NX Outline Dimension
Z=0
Tilt
Z=34.7(1.37)
Z=43.0(1.69)
Z=44.0(1.73)(4x)
M4x10(4x)
S2721H/HN/NX Outline Dimension Unit : mm(inch)
Dimension : Norminal
Drawing : Not to scale
Tilt
Z=0
Z=34.7(1.37)
M4x10(4x)
Z=43.0(1.69)
Z=44.0(1.73) (4x)
609.9
[24.01]
597.9
[23.54]
363.6
[14.32]
336.3
[13.24]
453.3
[17.85]
21.3
[0.84]
6.0
[0.24]
6.0
[0.24]
6.0
[0.24]
54.0
[2.12]
14.3
[0.56]
1.8
[0.07]
111.0
[4.37]
14.9
[0.59]
95.9
[3.78]
176.0
[6.93]
186.8
[7.35]
60.7
[2.39]
164.1
[6.46]
155.1
[6.11]
122.0 (2x)
[4.80]
100.0(2x)
[3.94]
15.1
[0.59]
445.4
[17.54]
88.2
[3.47]
9.0
[0.36]
450.0
[17.72]
42.5
[1.67]
191.7
[7.55]
5
21
257.2
[10.13]