Dell St2420l Users Guide

							 
Notes, Notices, and Cautions  
Information in this document is subject to change without notice.  
 
Reproduction of these materials in any manner whatsoever without the written permission of Dell Inc.   is strictly forbidden.  
Trademarks used in this text:  Dell  and the  DELL  logo   are trademarks of Dell Inc.  Microsoft  and  Windows  are either trademarks or registered trademarks of Microsoft Corporation in 
the United States and/or other countries;  ENERGY STAR  is a registered trademark of the U.S. Environmental Protection Agency. As an ENERGY STAR partner, Dell Inc. has 
determined that this product meets the ENERGY STAR guidelines for energy efficiency.  
Other trademarks and trade names may be used in this document to refer to either the entities claiming the marks and names or their products. Dell Inc. disclaims any 
proprietary interest in trademarks and trade names other than its own.  
ST2420Lb/ST2421Lb  
 
   
   About Your Monitor  
Setting Up the Monitor  
Operating the Monitor  
Solving Problems  
Appendix    
NOTE:  A NOTE indicates important information that helps you make better use of your computer. 
NOTICE:  A NOTICE indicates either potential damage to hardware or loss of data and tells you how to avoid the problem. 
  CAUTION:  A CAUTION indicates a potential for property damage, personal injury, or death.  
						

							Back to Contents Page    
    
 
 
   Package Contents  
   Product Features  
   Identifying Parts and Controls  
   Monitor Specifications  
   Plug and Play Capability  
   LCD Monitor Quality & Pixel Policy  
   Maintenance Guidelines  
Package Contents  
Your monitor ships with the components shown below. Ensure that you have received all the components and  contact Dell  if something 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.
    l Monitor with Stand   
  l Power Cable  
   
  l DVI Cable (optional)   
   
l VGA Cable     
						

							   
Product Features  
The  ST2420L/ST2421L  flat panel display has an active matrix, Thin - Film Transistor (TFT), and Liquid Crystal Display (LCD). The monitor features include:  
■   ST2420L/ST2421L:  60.97cm (24 inches) viewable area display.   
■  1920 x 1080 resolution, plus full - screen support for lower resolutions.   
■  Tilt adjustment capability.   
■  Plug and play capability if supported by your system.   
■  On - Screen Display (OSD) adjustments for ease of set - up and screen optimization.   
■  Software and documentation CD which includes an information file (INF), Image Color Matching File (ICM), and product documentation.    
■  Energy Saver feature for Energy Star compliance.    
■  Security lock slot.    
Identifying Parts and Features  
Front View  
   
Back View     l Safety Information   
l Drivers and Documentation  media 
l Quick Setup Guide    
Front View Front Panel Controls
Label Description
1 - 2 Shortcut keys 
*The default settings are Preset Modes  and Brightness/Contrast.   
1 Shortcut key: Preset Modes (Default)
2 Shortcut key: Brightness/Contrast (Default)
3 OSD menu select
4 EXIT
5 Power On/Off (light indicator below Dell logo)  
						

							 
Side View  
Bottom View  
  Label Description/Use  
1 Barcode serial number label To contact Dell for technical support.
2 Security lock slot To help secure your monitor.
3 Dell Soundbar mounting brackets To attach the optional Dell Soundbar.
4 Regulatory rating label Lists the regulatory approvals.
5 Stand release button To release stand assembly from monitor.
 
   Left Side  
						

							   
Monitor Specifications  
Power Management Modes  
If you have VESA's DPMS™ compliance display card or software installed in your PC, the monitor can automatically reduce its power consumption when not in 
use. This is referred to as Power Save Mode. If input from a keyboard, mouse or other input devices is detected by the computer, the monitor will automatically 
wake up. The following table shows the power consumption and signaling of this automatic power - saving feature:   
ST2420L/ST2421L  
Pin Assignments  
VGA Connector  
   
Bottom view  
Label Description
1 AC power cord connector
2 DVI connector
3 HDMI connector
4 VGA connector
5 Audio Line - in
6 Audio Line out
VESA Modes   Horizontal 
Sync   Vertical Sync   Video   Power 
Indicator   Power Consumption  
Normal operation   Active   Active   Active   White   30 W (maximum)  
20 W (typical)  
Active - off mode   Inactive   Inactive   Blanked   Amber   Less than 1 W  
Switch off   -     -     -     Off   Less than 0.5 W  
NOTE:   This monitor is ENERGY STAR ®
- compliant.
NOTE:  Zero power consumption in OFF mode can only be achieved by disconnecting the main cable from the 
monitor.    
Pin 
Number   15 - pin Side of the 
Connected Signal Cable    
						

							 
 1   Video - Red    
2   Video - Green  
3   Video - Blue  
4   GND  
5   Self - test  
6   GND - R  
7   GND - G  
8   GND - B  
9   Computer 5V/3.3V  
10   GND - sync  
11   GND  
12   DDC data  
13   H - sync  
14   V - sync  
15   DDC clock  
Pin 
Number 24 - pin Side of th e C o nnected  Signal 
Cable
1 TMDS RX2 -
2 TMDS RX2+
3 TMDS Ground
4 Floating
5 Floating
6 DDC Clock
7 DDC Data
8 Floating
9 TMDS RX1 -
10 TMDS RX1+
11 TMDS Ground
12 Floating
13 Floating
14 +5V power
15 Self test 
16 Hot Plug Detect
17 TMDS RX0 -
18 TMDS RX0+
19 TMDS Ground
20 Floating
21 Floating
22 TMDS Ground
23 TMDS Clock+
24 TMDS Clock -  
						

							HDMI Connector  
   
Flat Panel Specifications  
* Based on estimation  
** ST2420L/ST2421L Color Gamut (Typical) is based on CIE1976 (81 %) and CIE1931 (68 %).  Pin Number   19 - pin Side of the Connected Signal Cable  
1 TMDS DATA 2+
2 TMDS DATA 2 SHIELD
3 TMDS DATA 2 -
4 TMDS DATA 1+ 
5 TMDS DATA 1 SHIELD
6 TMDS DATA 1 -
7 TMDS DATA 0+
8 TMDS DATA 0 SHIELD
9 TMDS 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 +5V POWER
19 HOT PLUG DETECT
Model ST2420L/ST2421L
Screen type Active matrix  -  TFT LCD
Panel type TN
Screen dimensions 60.97cm (24 inches) (24 - inch viewable image size)
Preset display area:   
Horizontal    
Vertical      
531.36 mm (20.92 inches)   
298.89 mm (11.77 inches)  
Pixel pitch 0.277 mm
Viewing angle 160° (verticalyfW\SLFDO
						

							Resolution  
   
Video Supported Modes  
   
Preset Display Modes  
ST2420L/ST2421L  
   
Electrical  
   
Physical Characteristics  Model ST2420L/ST2421L
Horizontal scan range 30 kHz to 83 kHz (automatic)
Vertical scan range 56 Hz to 76 Hz (automaticyf
Maximum preset resolution 1920 x 1080 at 60 Hz
Model ST2420L/ST2421L
Video display capabilities (HDMI playback) 480i/480p/576i/576p/720p/1080i/1080p     
Display Mode   Horizontal Frequency 
(kHz)   Vertical Frequency 
(Hz)   Pixel Clock 
(MHz)   Sync Polarity (Horizontal/Vertical)  
VGA, 720 x 400   31. 469   70.0 87   28.3   - /+  
VGA, 640 x 480   31. 469   59.940   25.2   - / -  
VGA , 640 x 480   37.5 00   75.0 00   31.5   - / -  
VESA, 800 x 600   37. 879   60.3 17   40.0   +/+  
VESA, 800 x 600   46. 875   75.0 00   49.5   +/+  
VESA, 1024 x 768   48. 363   60.0 04   65.0   - / -  
VESA, 1024 x 768   60.0 23   75.0 29   78.8   +/+  
VESA. 1152 x 864  67.500  75.000  108.0  +/+ 
VESA,  1 280 x 1024     64.000   60.000   108.0   +/+  
VESA,  1 280 x 1024   79.976   75.025   135.0   +/+  
VESA, 1920 x 1080 67.500 60.000 148.5 +/+
Model ST2420L/ST2421L
Video input signals Analog RGB, 0.7 Volts +/ -  5%, positive polarity at 75 ohm input impedance   
D igital DVI - D TMDS, 600mV for each differential line, positive polarity at 50 ohm input 
impedance   
HDMI, 600mV 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/frequency/current 100 to 240 VAC/50 or 60 Hz  +  3 Hz/2.0A (Max.)
Inrush iso surge current 120 V: 30 A (Max.)  
240 V: 60 A (Max.) 
Model ST2420L/ST2421L
Connector type l D - sub: Blue connector   
l DVI - D: White connector   
l HDMI   
Signal cable type l D - sub: Detachable, Analog, 15 pin, shipped attached to the monitor   
l DVI - D   
l HDMI     
						

							   
Environmental  
   
Plug and Play Capability  
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 that the system can configure itself and optimize the monitor settings. If required, 
the user can select different settings, but in most cases monitor installation is automatic.  
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. The visible result is a fixed 
pixel that appears as an extremely tiny dark or bright discolored spot. When the pixel remains permanently lit, it is known as a bright dot. When the pixel 
remains black, it is known as a dark dot.    
In almost every case, these fixed pixels are hard to see and do not detract from display quality or usability. A display with 1 to 5 fixed pixels is considered 
normal and within competitive standards.  For more information, see Dell Support site at:  support.dell.com .  
Maintenance Guidelines  Dimensions (with stand)
Height 418.24  mm ( 16.47  inches)
Width 574.96 mm (22.64 inches)
Depth 203.68  mm ( 8.02 inches)
Dimensions (without stand)
Height  356.43 mm  ( 14.03 inches)
Width 574.96 mm (22.64 inches)
Depth 59.72  mm ( 2.35  inches)
Stand dimensions
Height 149.85 mm  (  5.90 inches)
Width 203.68  mm (8.02 inches)
Depth 203.68  mm (8.02 inches)
Weight
Weight with packaging 5.75 kg (12.68 lb)
Weight with stand assembly and 
cables 4.29 kg (9.46 lbyf 
Weight without stand assembly  
(f or wall mount or VESA mount 
considerations  -  no cables) 3.65 kg (8.05 lb)
Weight of stand assembly 0.64 kg  ( 1.41 lb)
Model ST2420L/ST2421L
Temperature
Operating 0° to 40° C (32° to 104°Fyf
Non - operating Storage:  - 20° to 60° C ( - 4° to 140° Fyf  
Shipping:  - 20° to 60° C ( - 4° to 140° Fyf
Humidity
Operating 10% to 80% (non - condensing)
Non - operating Storage: 5% to 90% (non - condensing)  
Shipping: 5% to 90% (non - condensing)
Altitude
Operating 4,485 m (14,700 ft) max
Non - operating 12,191 m (40,000 ft) max
Thermal dissipation 102.36 BTU/hour (maximum)  
68.24 BTU/hour (typical)  
						

							Caring for Your Monitor  
Fo r best practices, follow the instructions in the list below while unpacking, cleaning, or handling your monitor:  
l To clean your antistatic screen, lightly 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.   
l 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.    
l If you notice a white powder when you unpack your monitor, wipe it off with a cloth.   
l Handle your monitor with care as dark - colored monitors may scratch and show white scuff marks more than lighter - colored monitors.     
l 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.   
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      CAUTION:   Read and follow the  Safety Instructions  before cleaning the 
 
  CAUTION:   Before cleaning the monitor, unplug the monitor from the electrical