DELL D2721H User Manual

Dell Monitor  
D2421H/D2721H/D2421DS  
User’s Guide  
Monitor Model: D2421H/D2721H/D2421DS  
Regulatory Model: D2421Ho/D2721Ho/D2421DSo  
Contents  
About Your Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5  
Package Contents . . . . . . . . . . . . . . . . . . . . . . 5  
Product Features. . . . . . . . . . . . . . . . . . . . . . . 6  
Identifying Parts and Controls. . . . . . . . . . . . . . . . 7  
Monitor Specifications. . . . . . . . . . . . . . . . . . . 11  
Plug and Play. . . . . . . . . . . . . . . . . . . . . . . . 23  
LCD Monitor Quality & Pixel Policy . . . . . . . . . . . . 23  
Setting Up the Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24  
Connecting the stand . . . . . . . . . . . . . . . . . . . 24  
Using the Tilt and Vertical Extension . . . . . . . . . . . 26  
Rotating the Monitor. . . . . . . . . . . . . . . . . . . . 27  
Connecting Your Monitor . . . . . . . . . . . . . . . . . 28  
Removing the Monitor Stand . . . . . . . . . . . . . . . 29  
Wall Mounting (Optional) . . . . . . . . . . . . . . . . . 31  
Operating the Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32  
Power On the Monitor . . . . . . . . . . . . . . . . . . . 32  
Using the Front-Panel Controls . . . . . . . . . . . . . . 32  
Using the OSD Lock function . . . . . . . . . . . . . . . 33  
Using the On-Screen Display (OSD) Menu . . . . . . . . 33  
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41  
Common Problems. . . . . . . . . . . . . . . . . . . . . 41  
3
Product-Specific Problems . . . . . . . . . . . . . . . . 44  
Appendix. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45  
Safety Instructions. . . . . . . . . . . . . . . . . . . . . 45  
Contact Dell . . . . . . . . . . . . . . . . . . . . . . . . 45  
Setting Up Your Monitor . . . . . . . . . . . . . . . . . . 45  
Setting Up Your Monitor . . . . . . . . . . . . . . . . . . 47  
Maintenance Guidelines . . . . . . . . . . . . . . . . . . 49  
4
About Your Monitor  
Package Contents  
Your monitor ships with all the components shown below. Ensure that you have received  
all the components and Contact Dell if anything is missing.  
NOTE: Some items may be optional and may not ship with your monitor. Some  
features or media may not be available in certain countries.  
Display  
a
b
a. D2421DS  
b. D2421H/D2721H  
Stand Riser  
a. D2421DS  
b. D2421H  
c. D2721H  
a
b
c
Stand base  
a. D2421DS  
b. D2421H  
a
b
c
c. D2721H  
Screws x 2 (D2721H)  
Power Cable  
HDMI Cable  
About Your Monitor  
5
Quick Setup Guide  
Safety and Regulatory  
Information  
Product Features  
The Dell D2421H/D2721H/D2421DS flat-panel display has an active matrix, Thin-Film  
Transistor (TFT), Liquid Crystal Display (LCD) Panel with LED backlight. The monitor  
features include:  
D2421H: 60.5 cm (23.8 in.) diagonal viewable image size, 1920 x 1080 resolution,  
plus full-screen support for lower resolutions.  
D2721H: 68.6 cm (27 in.) diagonal viewable image size, 1920 x 1080 resolution, plus  
full-screen support for lower resolutions.  
D2421DS: 60.5 cm (23.8 in.) diagonal viewable image size, 2560 x 1440 resolution,  
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.  
D2421H/D2721H: Digital connectivity with HDMI and Analog connectivity with  
VGA.  
D2421DS: Digital connectivity with DisplayPort and HDMI.  
Height adjustment and pivot capability for D2421DS.  
Plug and play capability if supported by your system.  
On-Screen Display (OSD) adjustments for ease of set-up and screen optimization.  
Security lock slot.  
RoHS compliant.  
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. TÜV-  
certified ComfortView feature is designed to reduce the amount of blue light  
emitted from the monitor to help optimize eye comfort.  
Arsenic-free glass and Mercury-free for the panel only.  
0.5 W standby power when in the sleep mode.  
6
About Your Monitor  
Identifying Parts and Controls  
NOTE: The graphics are used for the purpose of illustration only. Appearance on  
the computer may vary.  
D2421H  
Front view  
1
2
3
Label Description  
1
Function buttons (For more information, see Operating the Monitor)  
2
3
Power On/Off button  
LED indicator  
Back view  
1
2
DELL  
D2421H  
DELL  
D2421H  
  
  
  
  
  
  
⏨Წᱴ⽰ಞ/Flat Panel Monitor  
ශਭꢀModel No.: D2421H  
ޛ
⭫Ⓠ/ Rating:  
⏨Წᱴ⽰ಞ/Flat Panel Monitor  
ශਭꢀModel No.: D2421H  
ޛ
⭫Ⓠ/ Rating:  
100-240V~ 50/60Hz 0.8A  
100-240V~ 50/60Hz 0.8A  
  
  
  
  
  
  
3
䙖൦ꢁѣളꢀ Made in China  
䙖ᰛᵕꢀ Manufactured date: April 2020  
䙖൦ꢁѣളꢀ Made in China  
䙖ᰛᵕꢀ Manufactured date: April 2020  
4
Back View with Monitor Stand  
Label Description  
Use  
1
VESA mounting holes (100 mm)  
Supports optional mounting of the monitor  
using a VESA mount or arm.  
2
Security lock slot  
Secures monitor with security lock  
(security lock not included).  
About Your Monitor  
7
3
4
Regulatory rating label with  
Barcode serial number  
Lists the regulatory approvals. Refer to  
this label if you need to contact Dell for  
technical support.  
Stand release button  
Release stand from monitor.  
Bottom View  
1
2 3 4  
Label Description  
Use  
1
AC power connector To connect the monitor power cable.  
2
HDMI connector  
To connect your computer to the monitor using a HDMI  
cable.  
3
VGA connector  
To connect your computer to the monitor using a VGA  
cable.  
4
Earphone connector  
To connect your earphone  
D2721H  
Front view  
1
2
3
Label Description  
1
Function buttons (For more information, see Operating the Monitor)  
8
About Your Monitor  
2
3
Power On/Off button  
LED indicator  
Back view  
1
DELL  
D2721H  
2
3
DELL  
D2721H  
  
  
  
  
  
  
⏨Წᱴ⽰ಞ/Flat Panel Monitor  
ශਭꢀModel No.: D2721H  
ޛ
⭫Ⓠ/ Rating:  
⏨Წᱴ⽰ಞ/Flat Panel Monitor  
ශਭꢀModel No.: D2721H  
ޛ
⭫Ⓠ/ Rating:  
100-240V~ 50/60Hz 1.0A  
100-240V~ 50/60Hz 1.0A  
  
  
  
  
  
  
䙖൦ꢁѣളꢀ Made in China  
䙖൦ꢁѣളꢀ Made in China  
䙖ᰛᵕꢀ Manufactured date: April 2020  
䙖ᰛᵕꢀ Manufactured date: April 2020  
4
Back View with Monitor Stand  
Label Description  
Use  
1
VESA mounting holes (100 mm)  
Supports optional mounting of the monitor  
using a VESA mount or arm.  
2
3
Security lock slot  
Secures monitor with security lock  
(security lock not included).  
Regulatory rating label with  
Barcode serial number  
Lists the regulatory approvals. Refer to  
this label if you need to contact Dell for  
technical support.  
4
Stand release button  
Release stand from monitor.  
Bottom View  
1
2 3  
Label Description  
Use  
1
AC power connector To connect the monitor power cable.  
About Your Monitor  
9
2
3
HDMI connector  
VGA connector  
To connect your computer to the monitor using a HDMI  
cable.  
To connect your computer to the monitor using a VGA  
cable.  
D2421DS  
Front view  
1
2
3
Label Description  
1
Function buttons (For more information, see Operating the Monitor)  
2
3
Power On/Off button  
LED indicator  
Back view  
1
2
3
Back View with Monitor Stand  
10  
About Your Monitor  
Label Description  
Use  
1
VESA mounting holes (100 mm)  
Supports optional mounting of the monitor  
using a VESA mount or arm.  
2
3
Security lock slot  
Secures monitor with security lock  
(security lock not included).  
Regulatory rating label with  
Barcode serial number  
Lists the regulatory approvals. Refer to  
this label if you need to contact Dell for  
technical support.  
Bottom View  
1
2
3
Label Description  
Use  
1
AC power connector To connect the monitor power cable.  
2
HDMI connector  
To connect your computer to the monitor using a HDMI  
cable.  
3
DP connector  
To connect your computer to the monitor using a DP  
cable.  
Monitor Specifications  
Flat-Panel Specifications  
Model number  
D2421H  
Active matrix - TFT LCD  
D2721H  
Screen type  
Panel type  
Active matrix - TFT LCD  
In-Plane Switching  
Technology  
In-Plane Switching  
Technology  
Viewable image  
Diagonal  
604.7 mm (23.8 in.)  
527.04 mm (20.76 in.)  
296.46 mm (11.67 in.)  
686.0 mm (27 in.)  
Horizontal Active Area  
Vertical Active Area  
Area  
597.89 mm (23.54 in.)  
336.31 mm (13.24 in.)  
156246.27 mm² (242.27 in.²) 201076.91 mm² (311.67 in.²)  
Pixel pitch  
0.2745 x 0.2745 mm  
0.3114 x 0.3114 mm  
About Your Monitor  
11  
Pixel per inch (PPI)  
92  
81  
Viewing angle  
Horizontal  
Vertical  
178° (typical)  
178° (typical)  
178° (typical)  
178° (typical)  
Brightness  
Contrast ratio  
250 cd/m² (typical)  
1000 to 1 (typical)  
250 cd/m² (typical)  
1000 to 1 (typical)  
Faceplate coating  
Anti-glare with hard-coating  
3H hardness  
Anti-glare with hard-coating  
3H hardness  
Backlight  
White LED edgelight system  
White LED edgelight system  
Response Time  
5 ms (gray to gray - fast  
mode)  
5 ms (gray to gray - fast  
mode)  
8 ms (gray to gray - normal  
mode)  
8 ms (gray to gray - normal  
mode)  
Color Depth  
Color Gamut  
16.7 mil colors  
16.7 mil colors  
72% NTSC(CIE 1931)  
72% NTSC(CIE 1931)  
and 83% NTSC(CIE 1976)  
and 83% NTSC(CIE 1976)  
Connectivity  
1x VGA, 1x HDMI 1.4, 1x  
1x VGA, 1x HDMI 1.4  
Earphone (φ 3.5 mm)  
Border width (edge of  
monitor to active area) (Top)/22.26 mm (Bottom)  
6.25 mm (Side)/6.24 mm  
6.98 mm (Side)/6.98 mm  
(Top)/20.90 mm (Bottom)  
Adjustability  
Height adjustable stand N/A  
N/A  
Tilt  
-5° to 20°  
N/A  
-5° to 20°  
N/A  
Pivot  
Security  
Security lock slot (cable lock Security lock slot (cable lock  
sold separately)  
sold separately)  
Model number  
Screen type  
Panel type  
D2421DS  
Active matrix - TFT LCD  
In-Plane Switching Technology  
Viewable image  
Diagonal  
604.5 mm (23.8 in.)  
Horizontal Active Area  
Vertical Active Area  
Area  
526.85 mm (20.74 in.)  
296.35 mm (11.67 in.)  
156132.00 mm² (242.03 in.²)  
12  
About Your Monitor  
Pixel pitch  
0.2058 x 0.2058 mm  
123  
Pixel per inch (PPI)  
Viewing angle  
Horizontal  
Vertical  
178° (typical)  
178° (typical)  
Brightness  
300 cd/m² (typical)  
Contrast ratio  
1000 to 1 (typical)  
Faceplate coating  
Anti-glare with hard-coating 3H hardness  
Backlight  
White LED edgelight system  
Response Time  
5 ms (gray to gray - fast mode)  
8 ms (gray to gray - normal mode)  
Color Depth  
Color Gamut  
Connectivity  
16.7 mil colors  
99% sRGB(TYP)  
3x HDMI 1.4, 1x DP 1.2  
Border width (edge of  
monitor to active area)  
7.08 mm (Side)/7.02 mm (Top)/19.83 mm (Bottom)  
Adjustability  
Height adjustable stand 100 mm  
Tilt  
-3.5° to 21.5°  
Pivot  
Security  
90° clockwise  
Security lock slot (cable lock sold separately)  
Resolution Specifications  
Model number  
D2421H/D2721H  
D2421DS  
Scan range  
• Horizontal  
• Vertical  
30 kHz to 83 kHz (automatic)  
50 Hz to 75 Hz (automatic)  
30 kHz to 83 kHz (automatic)  
50 Hz to 75 Hz (automatic)  
Maximum preset  
resolution  
1920 x 1080 at 60 Hz  
2560 x 1440 at 60 Hz  
About Your Monitor  
13  
Video display  
capabilities  
( HDMI&DP  
playback)  
480i, 480p, 576i, 576p, 720p,  
1080i, 1080p  
480i, 480p, 576i, 576p, 720p,  
1080i, 1080p  
Preset Display Modes  
The following table lists the preset modes for which Dell guarantees image size and  
centering:  
D2421H/D2721H  
Horizontal  
Frequency  
(kHz)  
Vertical  
Frequency  
(Hz)  
Sync Polarity  
(Horizontal/  
Vertical)  
Pixel Clock  
(MHz)  
Display Mode  
VESA, 720 x 400  
VESA, 640 x 480  
VESA, 640 x 480  
VESA, 800 x 600  
VESA, 800 x 600  
VESA, 1024 x 768  
VESA, 1024 x 768  
VESA, 1152 x 864  
VESA, 1280 x 1024  
VESA, 1280 x 1024  
VESA, 1600 x 900  
VESA, 1920 x 1080  
31.5  
31.5  
37.5  
37.9  
46.9  
48.4  
60.0  
67.5  
64.0  
80.0  
60.0  
67.5  
70.1  
59.9  
75.0  
60.3  
75.0  
60.0  
75.0  
75.0  
60.0  
75.0  
60.0  
60.0  
28.3  
25.2  
31.5  
-/+  
-/-  
-/-  
40.0  
49.5  
65.0  
78.8  
+/+  
+/+  
-/-  
+/+  
+/+  
+/+  
+/+  
+/+  
+/+  
108.0  
108.0  
135.0  
108.0  
148.5  
D2421DS  
Horizontal  
Frequency  
(kHz)  
Vertical  
Frequency  
(Hz)  
Sync Polarity  
(Horizontal/  
Vertical)  
Pixel Clock  
(MHz)  
Display Mode  
VESA, 720 x 400  
VESA, 640 x 480  
VESA, 640 x 480  
31.5  
31.5  
37.5  
70.1  
59.9  
75.0  
28.3  
25.2  
31.5  
-/+  
-/-  
-/-  
14  
About Your Monitor  
VESA, 800 x 600  
VESA, 800 x 600  
VESA, 1024 x 768  
VESA, 1024 x 768  
VESA, 1152 x 864  
VESA, 1280 x 1024  
VESA, 1280 x 1024  
VESA, 1600 x 900  
VESA, 1920 x 1080  
VESA, 1920 x 1200  
VESA, 2560 x 1440  
37.9  
46.9  
48.4  
60.0  
67.5  
64.0  
80.0  
60.0  
67.5  
74.0  
88.8  
60.3  
75.0  
60.0  
75.0  
75.0  
60.0  
75.0  
60.0  
60.0  
60.0  
60.0  
40.0  
49.5  
+/+  
+/+  
-/-  
65.0  
78.8  
+/+  
+/+  
+/+  
+/+  
+/+  
+/+  
+/+  
+/-  
108.0  
108.0  
135.0  
108.0  
148.5  
154.0  
241.5  
Electrical Specifications  
Model number  
D2421H  
Video input signals • Analog RGB: 0.7 V 5 %, 75 ohm input impedance  
• HDMI 1.4 (HDCP 1.4), 150 mV=<Vp-p=<1560 mV for each  
differential line, 100 ohm input impedance per differential pair  
Synchronization  
input signals  
Separate horizontal and vertical synchronizations, polarity-free  
TTL level, SOG (Composite SYNC on green)  
AC input voltage / 100 VAC to 240 VAC / 50 Hz or 60 Hz 3 Hz / 0.8 A (typical)  
frequency / current  
Inrush current  
120 V: 30 A (Max.)  
240 V: 60 A (Max.)  
Model number  
D2721H  
Video input signals • Analog RGB: 0.7 V 5 %, 75 ohm input impedance  
• HDMI 1.4 (HDCP 1.4), 150 mV=<Vp-p=<1560 mV for each  
differential line, 100 ohm input impedance per differential pair  
Synchronization  
input signals  
Separate horizontal and vertical synchronizations, polarity-free  
TTL level, SOG (Composite SYNC on green)  
About Your Monitor  
15  
AC input voltage / 100 VAC to 240 VAC / 50 Hz or 60 Hz 3 Hz / 1.0 A (typical)  
frequency / current  
Inrush current  
120 V: 30 A (Max.)  
240 V: 60 A (Max.)  
Model number  
D2421DS  
Video input signals • HDMI 1.4 (HDCP 1.4), 150 mV=<Vp-p=<1560 mV for each  
differential line, 100 ohm input impedance per differential pair  
• DisplayPort 1.2 (HDCP 1.4), 120mV min.(For HBR) 50 mV min.  
(For HBR2) for each differential line, 100 ohm input impedance  
per differential pair  
Synchronization  
input signals  
Separate horizontal and vertical synchronizations, polarity-free  
TTL level, SOG (Composite SYNC on green)  
AC input voltage / 100 VAC to 240 VAC / 50 Hz or 60 Hz 3 Hz / 0.8 A (typical)  
frequency / current  
Inrush current  
120 V: 30 A (Max.)  
240 V: 60 A (Max.)  
Physical Characteristics  
The following table lists the monitor’s physical characteristics:  
Model number  
D2421H  
D2721H  
Signal cable type  
• Analog: D-Sub, 15 pins  
• Digital: HDMI, 19 pins  
• Analog: D-Sub, 15 pins  
• Digital: HDMI, 19 pins  
Dimensions: (with stand)  
Height  
393.7 mm (15.50 in.)  
539.5 mm (21.24 in.)  
176.9 mm (6.96 in.)  
478.5 mm (18.84 in.)  
611.8 mm (24.09 in.)  
236.9 mm (9.33 in.)  
Width  
Depth  
Dimensions: (without stand)  
Height  
325.3 mm (12.81 in.)  
539.5 mm (21.24 in.)  
40.8 mm (1.61 in.)  
364.2 mm (14.34 in.)  
611.8 mm (24.09 in.)  
47.6 mm (1.87 in.)  
Width  
Depth  
Stand dimensions:  
Height  
176.4 mm (6.94 in.)  
199.9 mm (7.87 in.)  
176.9 mm (6.96 in.)  
186.9 mm (7.36 in.)  
272.7 mm (10.74 in.)  
236.9 mm (9.33 in.)  
Width  
Depth  
16  
About Your Monitor  
Weight:  
Weight with packaging  
4.9 Kg (10.80 lb)  
6.0 Kg (13.23 lb)  
4.8 Kg (10.58 lb)  
Weight with stand assembly 3.8 Kg (8.38 lb)  
and cables  
Weight without stand  
3.2 Kg (7.05 lb)  
4.0 Kg (8.82 lb)  
0.5 Kg (1.10 lb)  
assembly (For wall mount or  
VESA mount considerations  
- no cables)  
0.3 Kg (0.66 lb)  
Weight of stand assembly  
Model number  
D2421DS  
Signal cable type  
• Digital: DisplayPort, 20 pins  
• Digital: HDMI, 19 pins  
Dimensions: (with stand)  
Height (extended)  
Height (compressed)  
Width  
505.7 mm (19.91 in.)  
405.7 mm (15.97 in.)  
541.0 mm (21.30 in.)  
211.6 mm (8.33 in.)  
Depth  
Dimensions: (without stand)  
Height  
323.2 mm (12.72 in.)  
541.0 mm (21.30 in.)  
44.9 mm (1.77 in.)  
Width  
Depth  
Stand dimensions:  
Height (extended)  
Height (compressed)  
Width  
391.9 mm (15.43 in.)  
347.22 mm (13.67 in.)  
214.6 mm (8.45 in.)  
Depth  
211.6 mm (8.33 in.)  
Base  
214.6 mm x 211.6 mm (8.45 in. x 8.33 in.)  
Weight:  
Weight with packaging  
7.0 Kg (15.43 lb)  
5.9 Kg (13.01 lb)  
Weight with stand assembly and cables  
Weight without stand assembly (For wall  
mount or VESA mount considerations - no 3.5 Kg (7.72 lb)  
cables)  
2.1 Kg (4.63 lb)  
Weight of stand assembly  
About Your Monitor  
17  
Environmental Characteristics  
Model number  
Temperature  
D2421H/D2721H/D2421DS  
• Operating  
0°C to 50°C (32°F to 122°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  
20 % to 90 % (non-condensing)  
• Operating  
• Non-operating  
Storage: 5 % to 90 % (non-condensing)  
Shipping: 5 % to 90 % (non-condensing)  
Altitude  
5,000 m (16,404 ft) max  
12,191 m (40,000 ft) max  
• Operating  
• Non-operating  
Model number  
D2421H  
D2721H  
D2421DS  
Thermal dissipation  
75.06 BTU/hour  
(maximum)  
95.53 BTU/hour  
(maximum)  
119.42 BTU/hour  
(maximum)  
68.24 BTU/hour  
(typical)  
85.3 BTU/hour  
(typical)  
102.36 BTU/hour  
(typical)  
Compliant standards  
Model number  
D2421H/D2721H/D2421DS  
RoHS Compliant  
yes  
BFR/PVC free Monitor (excluding external cables) no  
Power Management Modes  
If you have VESA’s DPM compliance display card or software installed in your PC, the  
monitor automatically reduces its power consumption when not in use. This is referred  
to as Power Save Mode. If the computer detects input from 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:  
D2421H  
VESA Modes  
Horizontal Vertical Video Power  
Power Consumption  
Sync  
Sync  
Indicator  
Normal operation Active  
Active  
Active BLUE  
22 W (maximum)**  
20 W (typical)  
18  
About Your Monitor  
Active-off mode Inactive  
Switch off  
Inactive Blank  
ORANGE Less than 0.5 W  
-
-
-
Off  
Less than 0.5 W *  
Power Consumption Pon  
14.7 W  
Total Energy Consumption (TEC) 45.7 kWh  
D2721H  
VESA Modes  
Horizontal Vertical Video Power  
Power Consumption  
Sync  
Sync  
Indicator  
Normal operation Active  
Active  
Active BLUE  
28 W (maximum)**  
25 W (typical)  
Active-off mode Inactive  
Inactive Blank  
ORANGE Less than 0.5 W  
Switch off  
-
-
-
Off  
Less than 0.5 W *  
Power Consumption Pon  
16.7 W  
Total Energy Consumption (TEC) 52.0 kWh  
D2421DS  
VESA Modes  
Horizontal Vertical Video Power  
Power Consumption  
Sync  
Sync  
Indicator  
Normal operation Active  
Active  
Active BLUE  
35 W (maximum)**  
30 W (typical)  
Active-off mode Inactive  
Inactive Blank  
ORANGE Less than 0.5 W  
Off Less than 0.5 W *  
Switch off  
-
-
-
Power Consumption Pon  
16.8 W  
Total Energy Consumption (TEC) 52.2 kWh  
NOTE:  
Pon : Power consumption of On Mode measured with reference to Energy Star test method.  
TEC : Total energy consumption in kWh measured with reference to Energy Star test method.  
The OSD operates only in the normal operation mode. In the active-off mode, you only  
could press button into Input Source.  
* 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 contrast.  
This document is informational only and reflects laboratory performance. Your product may  
perform differently, depending on the software, components and peripherals you ordered  
About Your Monitor  
19  
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 monitor to gain access to the OSD.  
Pin Assignments  
VGA connector  
1
2
3
4
5
6
7
8
9
10  
11 12 13 14 15  
Pin number 15-pin side of the connected signal cable  
1
2
Video-Red  
Video-Green  
Video-Blue  
GND  
3
4
5
Self-test  
GND-R  
6
7
GND-G  
8
GND-B  
9
DDC +5 V  
GND-sync  
GND  
10  
11  
12  
13  
14  
15  
DDC data  
H-sync  
V-sync  
DDC clock  
20  
About Your Monitor  
HDMI connector  
Pin number 19-pin Side of the Connected Signal Cable  
1
TMDS DATA 2+  
TMDS DATA 2 SHIELD  
TMDS DATA 2-  
2
3
4
TMDS DATA 1+  
TMDS DATA 1 SHIELD  
TMDS DATA 1-  
5
6
7
TMDS DATA 0+  
TMDS DATA 0 SHIELD  
TMDS DATA 0-  
TMDS CLOCK  
8
9
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
TMDS CLOCK SHIELD  
TMDS CLOCK-  
No Connection  
No Connection  
DDC CLOCK (SCL)  
DDC DATA (SDA)  
GND  
+5 V POWER  
HOT PLUG DETECT  
About Your Monitor  
21  
DP connector  
Pin number 20-pin side of the connected signal cable  
1
2
ML_LANE3_N  
GND  
3
ML_LANE3_P  
ML_LANE2_N  
GND  
4
5
6
ML_LANE2_P  
ML_LANE1_N  
GND  
7
8
9
ML_LANE1_P  
ML_LANE0_N  
GND  
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
ML_LANE0_P  
GND  
GND  
AUX _CH_P  
GND  
AUX _CH_N  
HPD  
RETURN  
DP_PWR  
22  
About Your Monitor  
Plug and Play  
You can install the monitor in any Plug and Play compatible system. The monitor  
automatically provides the computer with its Extended Display Identification Data (EDID)  
using Display Data Channel (DDC) protocols so that the system 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 & 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: www.dell.com/pixelguidelines.  
About Your Monitor  
23  
Setting Up the Monitor  
Connecting the stand  
NOTE: The stand is not installed at the factory when shipped. (D2421H/D2721H)  
NOTE: The stand is installed at the factory when shipped. (D2421DS)  
NOTE: The graphics are used for the purpose of illustration only. Appearance on  
the computer may vary.  
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.  
To attach the monitor stand:  
D2421H  
1. Assemble the stand riser to stand base.  
a. Place the monitor stand base on a stable table top.  
b. Slide the monitor stand body in the downward direction into the stand base  
until it clicks into place.  
2. Attach the stand assembly to the monitor:  
a. Place the monitor on a soft cloth or cushion near the edge of desk.  
b. Align the stand assembly bracket to the monitor groove.  
c. Insert the bracket towards monitor until it locks in place.  
24  
Setting Up the Monitor  
D2721H  
1. Assemble the stand riser to stand base.  
a. Place the monitor stand base on a stable table top.  
b. Slide the monitor stand body in the downward direction into the stand base  
until it clicks into place.  
2. Attach the stand assembly to the monitor:  
a. Place the monitor on a soft cloth or cushion near the edge of desk.  
b. Align the stand assembly bracket to the monitor groove.  
c. Use a screwdriver to fully tighten the two screws to the top of the stand.  
D2421DS  
1. Remove the monitor’s protective cover and place the monitor with its display side  
facing downward.  
2. Insert the stand base blocks fully into the stand slot.  
3. Lift the screw handle and turn the screw clockwise.  
4. After fully tightening the screw, fold the screw handle flat within the recess.  
NOTE: Lift the monitor carefully to prevent it from slipping or falling.  
Setting Up the Monitor  
25  
Using the Tilt and Vertical Extension  
Tilt  
With the stand assembly, you can tilt the monitor for the most comfortable viewing  
angle.  
D2421H  
D2721H  
5°  
20°  
5°  
20°  
D2421DS  
3.5°  
21.5°  
26  
Setting Up the Monitor  
NOTE: The stand base is detached when the monitor is shipped from the  
factory.  
Vertical Extension  
NOTE: The stand extends vertically up to 100 mm. The figure below illustrates  
how to extend the stand vertically.  
100mm  
Rotating the Monitor  
Before you rotate the monitor, your monitor should be fully vertically extended and fully  
tilted up to avoid hitting the bottom edge of the monitor.  
90°  
Setting Up the Monitor  
27  
Connecting Your Monitor  
WARNING: Before you begin any of the procedures in this section, follow the  
NOTE: Do not connect all cables to the computer at the same time.  
NOTE: Dell monitors are designed to work optimally with Dell supplied inbox  
cables. Dell does not guarantee the video quality and performance when using  
non-Dell cables.  
NOTE: The graphics are used for the purpose of illustration only. Appearance on  
the computer may vary.  
To connect your monitor to the computer:  
1. Turn off your computer and disconnect the power cable.  
2. Connect the black VGA or HDMI or DP cable to the corresponding video port on the  
back of your computer.  
3. Connect the Earphone port.(D2421H)  
Connecting VGA/HDMI Cable and Earphone  
D2421H  
VGA  
HDMI  
Connecting VGA/HDMI Cable  
D2721H  
28  
Setting Up the Monitor  
VGA  
HDMI  
Connecting HDMI/DP Cable  
D2421DS  
DP  
HDMI  
Removing the Monitor Stand  
NOTE: To prevent scratches on the screen when removing the stand, ensure  
that the monitor is placed on a soft and clean surface.  
NOTE: The following procedure is applicable for the stand that shipped with  
your monitor.  
NOTE: The graphics are used for the purpose of illustration only. Appearance on  
the computer may vary.  
To remove the stand:  
D2421H  
1. Place the monitor panel on a soft cloth or cushion.  
2. Use a long screwdriver to push the release latch located in a hole just above the stand.  
3. Once the latch is released, remove the stand away from the monitor.  
Setting Up the Monitor  
29  
4. Press the tenons inwardly and pull the base from stand to remove.  
D2721H  
1. Place the monitor panel on a soft cloth or cushion.  
2. Use a screwdriver to loosen the two screws at the top of the stand, Use a long  
screwdriver to push the release latch located in a hole just above the stand.  
3. Once the latch is released, remove the stand away from the monitor.  
4. Press the tenons inwardly and pull the base from stand to remove.  
D2421DS  
1. Place the monitor panel on a soft cloth or cushion.  
2. Loosen the screw from the base.  
3. Use a screwdriver to loosen the four screws at the back of the monitor.  
4. Lift the stand up and away from the monitor.  
30  
Setting Up the Monitor  
Wall Mounting (Optional)  
DELL  
D2421H  
  
  
  
⏨Წᱴ⽰ಞ/Flat Panel Monitor  
ශਭꢀModel No.: D2421H  
ޛ
⭫Ⓠ/ Rating:  
100-240V~ 50/60Hz 0.8A  
  
  
  
䙖൦ꢁѣളꢀ Made in China  
䙖ᰛᵕꢀ Manufactured date: April 2020  
NOTE: (Screw dimension: M4 x 10 mm). Refer to the instructions that come with  
the VESA-compatible base mounting kit.  
1. Place the monitor panel on a soft cloth or cushion on a stable flat table.  
2. Remove the stand.  
3. Remove 4 screws from wall hanging hole. (D2421H/D2721H)  
4. Attach the mounting bracket from the wall mounting kit to the LCD.  
5. Mount the LCD on the wall by following the instructions that came with the base  
mounting kit.  
NOTE: For use only with UL-listed wallD-mount bracket with minimum weight/load  
bearing capacity of 9.6 Kg (21.16 lb) for D2421H, 12.0 Kg (26.46 lb) for D2721H, 10.8 Kg  
(23.81 lb) for D2421DS.  
Setting Up 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 keys on the front of the monitor to adjust the settings.  
1
2
3
4 5  
6
Front-Panel Button Description  
Use this button to launch the on-screen display (OSD).  
See Accessing the Menu System.  
Use this button to go back to the main menu or exit the  
OSD main menu.  
1
Use this button to select the next item down the list or  
decrease the setting value.  
2
3
When not in OSD menu, directly enters Contrast/Brightness.  
Use this button to select the next item up the list or increase  
the setting value.  
When not in OSD menu, directly enters Color Vision Mode.  
Use this button to select the OSD menu.  
When not in OSD menu, directly enters Input Source from a list  
of VGA, HDMI, Auto (D2421H/D2721H).  
4
When not in OSD menu, directly enters Input Source from a list  
of HDMI1, HDMI2, HDMI3, DP, Auto (D2421DS).  
32  
Operating the Monitor  
 
5
6
Use the Power button to turn the monitor On and Off.  
/
The blue LED indicates the monitor is On and fully functional.  
Using the OSD Lock function  
Button  
Description  
OSD Lock, press 10 seconds to lock, repeat press 10 seconds to  
unlock(when not in OSD menu)  
+
Power Lock, press 10 seconds to lock, repeat press 10 seconds  
to unlock(when not in OSD menu)  
+
Using the On-Screen Display (OSD) Menu  
Accessing the Menu System  
NOTE: Any changes you make using the OSD menu are automatically saved if  
you move to another OSD menu, exit the OSD menu, or wait for the OSD menu  
to disappear.  
Press the button to open the OSD menu and display the main menu.  
Menu and  
Submenus  
Icon  
Description  
Auto Adjust  
(D2421H/  
D2721H)  
Adjust the Horizontal Position, Vertical Position, Phase (Fine  
Tune) and Clock (H. Size) of the screen.  
NOTE: Only available for D-SUB input.  
D2421H  
D2721H  
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Operating the Monitor  
33  
Contrast/  
Brightness  
Use the Contrast/Brightness menu to adjust the Contrast/  
Brightness/DCR/ECO.  
D2421H  
D2721H  
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D2421DS  
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Contrast  
Adjust brightness first, and adjust contrast only if you need  
further adjustment.  
Press the key to increase contrast and press the key to  
decrease contrast (min 0 ~ max 100).  
Brightness  
Brightness adjusts the luminance of the backlight(min 0 ~ max  
100).  
Press the button to decrease brightness.  
Press the button to increase brightness.  
DCR  
ECO  
To set DCR function on/off. If DCR on, brightness should be at  
100 and should not be adjustable.  
To control ECO function on/off. If ECO on, brightness should  
be at 20 and should not be adjustable. DCR should not be  
adjustable.  
34  
Operating the Monitor  
Input Source  
Use the Input Source menu to select between different video  
signals that may be connected to your monitor.  
D2421H  
D2721H  
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D2421DS  
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VGA  
HDMI  
DP  
Select VGA input when you are using the analog (VGA)  
connector. Push to select the VGA input source.  
Select HDMI input when you are using the HDMI connector.  
Push to select the HDMI input source.  
/
/
Select DP input when you are using the DP connector. Push  
to select the DP input source.  
Select Auto to scan for available input signals.  
/
Auto  
Operating the Monitor  
35  
 
Audio Adjust  
(only for  
D2421H)  
Use the Audio Settings menu to adjust the audio settings.  
When input source is VGA, “Audio Adjust” option on “Main  
Menu” can’t be selected.  
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Volume  
Push  
/
to adjust the earphone output scale.  
Mute  
To set or reset the mute function.  
Color Adjust  
When you select Color Adjust, you can choose Cool, Normal,  
Warm, ComfortView, User Color and Color Vision Mode from  
the list.  
D2421H  
D2721H  
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D2421DS  
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Operating the Monitor  
Cool  
Adds blue to screen image for cooler white.  
Normal  
Adds red to screen image for warmer white and richer  
red.  
Warm  
Adds green to screen image for a darker color.  
ComfortView Optimize eye comfort with a TÜV-certified flicker-free screen.  
Decreases the level of blue light emitted from the screen to  
make viewing more comfortable for your eyes.  
NOTE: To reduce the risk of eye strain and neck/arm/back/  
shoulders pain from using the monitor for long periods of  
time,we suggest that you:  
• Set the screen about 20~28 in. (50~70 cm) from your eyes.  
• Blink frequently to moisten or lubricate your eyes.  
Take regular 20-minute breaks every two hours.  
• Look away from your monitor and gaze at a distant object at  
20 feet away for at least 20 seconds during the breaks.  
• Perform stretches to relieve tension in the neck/arm/back/  
shoulders during the breaks.  
User Color  
Individual adjustments for red (R), green (G), blue (B).  
Each step will increase / decrease value by 1.  
Provides an optimum display environment depending on  
the contents displayed.To select Standard, Scenery, Game,  
Cinema, Text mode. When it is not under Standard mode,  
“Contrast/Brightness” option on “Main Menu” can’t be  
selected.  
Color Vision  
Mode  
Information  
When you select Information, displays the data about Model  
Name, Input Source, Resolution, H. Frequency, V. Frequency,  
Pixel Clock, Service Tag.  
Operating the Monitor  
37  
Manual Image When you select Manual Image Adjust, you can choose H./V.  
Adjust  
Position, Clock, Phase, Sharpness, Aspect Ratio and Response  
Time from the list. (D2421H/D2721H)  
D2421H  
D2721H  
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When you select Manual Image Adjust, you can choose  
Sharpness, Aspect Ratio and Response Time from the list.  
(D2421DS)  
D2421DS  
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H./V. Position To adjust the horizontal and vertical position of the video.  
Clock  
The Phase and Pixel Clock adjustments allow you to adjust  
your monitor to your preference.  
Phase  
If satisfactory results are not obtained using the phase  
adjustment, use the Clock (coarse) adjustment and then use  
Phase (fine), again.  
Sharpness  
To select the picture sharpness of display.  
Aspect Ratio  
To adjusts the video mode between Full Screen or 4:3  
Response  
Time  
Increase response time of panel. (Off/Normal/Fast)  
38  
Operating the Monitor  
Setup Menu  
When you select Setup Menu, you can choose Language  
Select, OSD Position, OSD Time Out and OSD Background  
from the list.  
D2421H  
D2721H  
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Language  
Set the OSD display to languages of English, Simplified  
Chinese.  
OSD Position Adjust the horizontal position of the OSD.  
Adjust the vertical position of the OSD.  
OSD Time Out To set the displaying time of OSD  
OSD  
Background  
Allows the user to change the OSD Transparency from  
0/20/40/60/80/100.  
Factory Reset Restore all preset values to the factory default settings.  
OSD Messages  
Activate the computer and wake up the monitor to gain access to the OSD.  
In the active-off mode, you only could press button into Input Source.  
Operating the Monitor  
39  
 
If VGA or DP or HDMI cable is not connected, a floating dialog box as shown below  
appears. The monitor will enter sleep mode, and the LED indicates color will be orange.  
No Signal  
See Troubleshooting for more information.  
40  
Operating the Monitor  
Troubleshooting  
WARNING: Before you begin any of the procedures in this section, follow the  
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 No picture  
off  
• 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 via the Input Source select  
button.  
No Video/Power LED No picture or no  
• Increase brightness & contrast controls  
via OSD.  
on  
brightness  
• Perform monitor self-test feature  
check.  
• Check for bent or broken pins in the  
video cable connector.  
• Ensure that the correct input source is  
selected via the Input Source select  
menu.  
Poor Focus  
Picture is fuzzy,  
• Perform Auto Adjust via OSD.  
blurry, or ghosting • Adjust the Phase and Pixel Clock  
controls via OSD.  
• Eliminate video extension cables.  
• Reset the monitor to Factory Reset.  
• Change the video resolution to the  
correct aspect ratio (16:9).  
Troubleshooting  
41  
 
Shaky/Jittery Video  
Wavy picture or fine • Perform Auto Adjust via OSD.  
movement  
• Adjust the Phase and Pixel Clock  
controls via OSD.  
• Reset the monitor to Factory Reset.  
• Check environmental factors.  
• Relocate the monitor and test in  
another room.  
Missing Pixels  
LCD screen has  
spots  
• Cycle power on-off.  
• Pixel that is permanently off is a  
natural defect that can occur in LCD  
technology.  
For more information on Dell Monitor  
Quality and Pixel Policy, see Dell Support  
site at:  
Stuck-on Pixels  
LCD screen has  
bright spots  
• Cycle power on-off.  
• 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:  
Brightness Problems Picture too dim or  
too bright  
• Reset the monitor to Factory Reset.  
• Auto Adjust via OSD.  
• Adjust brightness & contrast controls  
via OSD.  
Geometric Distortion Screen not  
• Reset the monitor to Factory Reset.  
centered correctly • Auto Adjust via OSD.  
• Adjust brightness & contrast controls  
via OSD.  
NOTE: When using ‘HDMI, the  
positioning adjustments are not  
available.  
42  
Troubleshooting  
Horizontal/Vertical  
Lines  
Screen has one or  
more lines  
• Reset the monitor to Factory Reset.  
• Perform Auto Adjust via OSD.  
• Adjust Phase and Pixel Clock controls  
via OSD.  
• Perform monitor self-test feature check  
and determine if these lines are also in  
self-test mode.  
• Check for bent or broken pins in the  
video cable connector.  
NOTE: When using ‘HDMI, the Pixel  
Clock and Phase adjustments are not  
available.  
Synchronization  
Problems  
Screen is scrambled • Reset the monitor to Factory Reset.  
or appears torn  
• Perform Auto Adjust via OSD.  
• Adjust Phase and Pixel Clock controls  
via OSD.  
• Perform monitor self-test feature check  
to determine if the scrambled screen  
appears in self-test mode.  
• Check for bent or broken pins in the  
video cable connector.  
• Restart the computer in the safe mode.  
Safety-Related Issues Visible signs of  
smoke or sparks  
• Do not perform any troubleshooting  
steps.  
• Contact Dell immediately.  
Intermittent Problems Monitor  
malfunctions on  
• Ensure that the video cable connecting  
the monitor to the computer is  
& off  
connected properly and is secure.  
• Reset the monitor to Factory Reset.  
• 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 feature  
check.  
• 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.  
Troubleshooting  
43  
Wrong Color  
Picture color not  
good  
• Change the Color Vision Mode in the  
Color Adjust OSD to Graphics or Video  
depending on the application.  
Try different User Color in Color Adjust  
OSD. Adjust R/G/B value in User Color  
OSD if the Color Vision Mode is turned  
off.  
NOTE: When choosing HDMI mode, the Auto Adjust function is not available.  
Product-Specific Problems  
Specific Symptoms What You  
Experience  
Possible Solutions  
Screen image is too  
small  
Image is centered  
• Check the Aspect Ratio setting in the  
Display OSD.  
• Reset the monitor to Factory Reset.  
on screen, but  
does not fill entire  
viewing area  
Cannot adjust the  
monitor with the  
buttons on the front  
panel  
OSD does not  
appear on the  
screen  
Turn off the monitor, unplug the power  
cord, plug back, and then turn on the  
monitor.  
• Check whether the OSD menu is  
locked. If yes, press the button and  
button for 10 seconds to unlock (for  
more information, see Lock).  
No Input Signal when No picture, the LED • Check the signal source. Ensure the  
user controls are  
pressed  
light is blue. When  
you press “up,  
“down” or “Menu”  
computer is not in the power saving  
mode by moving the mouse or pressing  
any key on the keyboard.  
key, the message “ • Check whether the signal cable is  
No input signal” will  
appear.  
plugged in properly. Re-plug the signal  
cable if necessary.  
• Reset the computer or video player.  
The picture does not The picture cannot • Due to different video formats (aspect  
fill the entire screen  
fill the height or  
width of the screen  
ratio) of DVDs, the monitor may display  
in full screen.  
44  
Troubleshooting  
Appendix  
Safety Instructions  
WARNING: 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.  
For information on safety instructions, see the Product Information Guide(SERI).  
Contact Dell  
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.  
To get online Monitor support content:  
To contact Dell for sales, technical support, or customer service issues:  
2. Verify your country or region in the Choose A Country/Region drop-down menu at  
the top-left corner of the page.  
3. Click Contact Us next to the country dropdown.  
4. Select the appropriate service or support link based on your need.  
5. Choose the method of contacting Dell that is convenient for you.  
Setting Up Your Monitor  
D2421H/D2721H  
Setting display resolution to 1920 x 1080  
For best performance, set the display resolution to 1920 x 1080 pixels by performing the  
following steps:  
In Windows Vista, 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.  
2.Right-click on the desktop and click Screen Resolution.  
3. Click the Dropdown list of the Screen Resolution and select 1920 x 1080.  
Appendix  
45  
   
4.Click OK.  
In Windows 10:  
1. Right-click on the desk top and click Display Settings.  
2. Click Advanced Display Settings.  
3. Click the drop-down menu under Resolution and select 1920 x 1080.  
4. Click Apply.  
If you do not see the recommended resolution as an option, you may need to update your  
graphics driver. Use one of the following methods to update the graphics driver:  
Dell computer  
1. Go to www.dell.com/support, enter your service tag, and download the latest  
driver for your graphics card.  
2. After installing the drivers for your graphics adapter, attempt to set the resolution  
to 1920 x 1080 again.  
NOTE: If you are unable to set the resolution to 1920 x 1080, please contact Dell to  
inquire about a graphics adapter that supports these resolutions.  
Non-Dell computer  
In Windows Vista, 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.  
2.Right-click on the desktop and click Personalization.  
3. Click Change Display Settings.  
4.Click Advanced Settings.  
5. Identify your graphics controller supplier from the description at the top of the  
window (e.g. NVIDIA, AMD, Intel etc.).  
6. Refer to the graphic card provider website for updated driver (for example, www.  
7. After installing the drivers for your graphics adapter, attempt to set the resolution  
to 1920 x 1080 again.  
In Windows 10:  
1. Right-click on the desktop and click Display Settings.  
2.Click Advanced display settings.  
46  
Appendix  
3. Click Display adapter properties.  
4.Identify your graphics controller supplier from the description at the top of the  
window (e.g. NVIDIA, AMD, Intel etc.).  
5. Refer to the graphic card provider website for updated driver (for example, www.  
6. After installing the drivers for your graphics adapter, attempt to set the resolution  
to 1920 x 1080 again.  
NOTE: If you are unable to set the recommended resolution, please contact the  
manufacturer of your computer or consider purchasing a graphics adapter that  
supports the video resolution.  
Setting Up Your Monitor  
D2421DS  
Setting display resolution to 2560 x 1440  
For best performance, set the display resolution to 2560 x 1440 pixels by performing the  
following steps:  
In Windows Vista, 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.  
2.Right-click on the desktop and click Screen Resolution.  
3. Click the Dropdown list of the Screen Resolution and select 2560 x 1440.  
4.Click OK.  
In Windows 10:  
1. Right-click on the desk top and click Display Settings.  
2. Click Advanced Display Settings.  
3. Click the drop-down menu under Resolution and select 2560 x 1440.  
4. Click Apply.  
If you do not see the recommended resolution as an option, you may need to update your  
graphics driver. Use one of the following methods to update the graphics driver:  
Appendix  
47  
Dell computer  
1. Go to www.dell.com/support, enter your service tag, and download the latest  
driver for your graphics card.  
2. After installing the drivers for your graphics adapter, attempt to set the resolution  
to 2560 x 1440 again.  
NOTE: If you are unable to set the resolution to 2560 x 1440, please contact Dell to  
inquire about a graphics adapter that supports these resolutions.  
Non-Dell computer  
In Windows Vista, 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.  
2.Right-click on the desktop and click Personalization.  
3. Click Change Display Settings.  
4.Click Advanced Settings.  
5. Identify your graphics controller supplier from the description at the top of the  
window (e.g. NVIDIA, AMD, Intel etc.).  
6. Refer to the graphic card provider website for updated driver (for example, www.  
7. After installing the drivers for your graphics adapter, attempt to set the resolution  
to 2560 x 1440 again.  
In Windows 10:  
1. Right-click on the desktop and click Display Settings.  
2.Click Advanced display settings.  
3. Click Display adapter properties.  
4.Identify your graphics controller supplier from the description at the top of the  
window (e.g. NVIDIA, AMD, Intel etc.).  
5. Refer to the graphic card provider website for updated driver (for example, www.  
6. After installing the drivers for your graphics adapter, attempt to set the resolution  
to 2560 x 1440 again.  
NOTE: If you are unable to set the recommended resolution, please contact the  
manufacturer of your computer or consider purchasing a graphics adapter that  
supports the video resolution.  
48  
Appendix  
Maintenance Guidelines  
Caring for 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 while unpacking, cleaning, or  
handling your monitor:  
To clean your antistatic screen, slightly dampen a soft, clean cloth with water. If  
possible, use a special screen-cleaning tissue or solution suitable for the antistatic  
coating. Do not use benzene, thinner, ammonia, abrasive cleaners, or compressed  
air.  
• Use a slightly dampened, warm cloth to clean the plastics. Avoid using detergent of  
any kind as some detergents leave a milky film on the plastics.  
• If you notice a white powder when you unpack your monitor, wipe it off with a  
cloth. This white powder occurs during the shipping of the monitor.  
• Handle your monitor with care as a darker-colored monitor may scratch 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 power off your monitor when not in use  
Appendix  
49  

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