Dell St2420l Users Guide

							 
4. Carefully inspect the screen for abnormalities.   
5. Press the  shortcut button 4  key on the front panel again. The color of the screen changes to red.   
6. Inspect the display for any abnormalities.   
7. Repeat steps 5 and 6 to inspect the display in green, blue, and white colored screens.   
The test is complete when the white screen appears. To exit, press the  shortcut button 4  again.   
If you do not detect any screen abnormalities upon using the built - in diagnostic tool, the monitor is functioning properly. Check the video card and computer.  
OSD Warning Messages  
For OSD - related issues, see  OSD Warning Messages .  
Common Problems  
The following table contains general information about common monitor problems that you might encounter and the possible solutions.   
Common Symptoms   What You Experience   Possible Solutions  
No Video/Power LED off No picture l Ensure that the video cable connecting the monitor and the computer is properly connected and 
secure.  
l Verify that the power outlet is functioning properly using any other electrical equipment.
l Ensure that the power button is depressed fully.    
No Video/Power LED on No picture or no brightness l Increase brightness & contrast controls via OSD.  
l Perform monitor self - test feature check.  
l Check for bent or broken pins in the video cable connector.    
l Run the built - in diagnostics.    
Poor Focus Picture is fuzzy, blurry, or ghosting l Perform Auto Adjust via OSD.  
l Adjust the Phase and Pixel Clock controls via OSD.  
l Eliminate video extension cables.  
l Reset the monitor to Factory Settings.  
l Change the video  resolution to the correct aspect ratio (16:9).  
Shaky/Jittery Video Wavy picture or fine movement l Perform Auto Adjust via OSD.  
l Adjust the Phase and Pixel Clock controls via OSD.  
l Reset the monitor to Factory Settings.  
l Check environmental factors.  
l Relocate the monitor and test in another room.    
Missing Pixels LCD screen has spots l Cycle power on - off.  
l Pixel that is permanently off is a natural defect that can occur in LCD technology.    
l Run the built - in diagnostics.    
Stuck - on Pixels LCD screen has bright spots l Cycle power on - off.  
l Pixel that is permanently off is a natural defect that can occur in LCD technology.    
l Run the built - in diagnostics.    
Brightness Problems Picture too dim or too bright l Reset the monitor to Factory Settings.  
l Auto Adjust via OSD.  
l Adjust brightness & contrast controls via OSD.    
Geometric Distortion Screen not centered correctly l Reset the monitor to Factory Settings.  
l Auto Adjust via OSD.  
l Adjust brightness & contrast controls via OSD.  
Horizontal/Vertical Lines Screen has one or more lines l Reset the monitor to Factory Settings.  
l Perform Auto Adjust via OSD.      
						

							   
Product - Specific Problems  
 
 l Adjust Phase and Pixel Clock controls via OSD.  
l Perform monitor self - test feature check and determine if these lines are also in self - test mode.
l Check for bent or broken pins in the video cable connector.    
l Run the built - in diagnostics.   
Synchronization Problems Screen is scrambled or appears 
torn l Reset the monitor to Factory Settings.  
l Perform Auto Adjust via OSD.  
l Adjust Phase and Pixel Clock controls via OSD.  
l Perform monitor self - test feature check to determine if scrambled screen appears in self
mode.  
l Check for bent or broken pins in the video cable connector.  
l Restart the computer in the  safe mode .    
Safety Related Issues Visible signs of smoke or sparks l Do not perform any troubleshooting steps.  
l Contact Dell immediately.   
Intermittent Problems Monitor turns on & off l Ensure that the video cable connecting the monitor to the computer is connected properly and is 
secure.  
l Reset the monitor to Factory Settings.  
l Perform monitor self - test feature check to determine if the intermittent problem occurs in self
mode.    
Missing Color Picture lacks color l Perform monitor self - test feature check.  
l Ensure that the video cable connecting the monitor to the computer is connected properly and is 
secure.  
l Check for bent or broken pins in the video cable connector.  
Wrong Color Picture color is not good l Change the Color Setting Mode in the Color Settings OSD to Graphics or Video depending to the 
application.   
l Try a different Color Preset Setting in Color Settings OSD. Adjust R/G/B value in Color Settings 
OSD if the Color Management is turned off.  
l Change the Input Color Format to PC RGB or YPbPr in the Advance Setting OSD.  
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 l Use the Power Management feature to turn off the monitor at all times when not in use
information, see  Power Management Modes ).  
l Alternatively, use a dynamically changing screensaver.    
SPECIFIC SYMPTOMS WHAT YOU EXPERIENCE POSSIBLE SOLUTIONS
Screen image is too small Image is centered on screen, but 
does not fill entire viewing area l Perform monitor reset on Factory Reset    
Cannot adjust the monitor with 
the buttons on the front panel OSD does not appear on the 
screen l Turn the monitor off and unplug the power cord and then plug back and power on    
No Input Signal when user 
controls pressed No picture, the LED light is 
amber. When control button is 
pressed, the message  No VGA 
cable,  No DVI - D cable or No 
HDMI cable will appear.  l Check the signal source. Ensure that the computer is not in power saving by moving the mouse 
or pressing any key on the keyboard.    
l Check whether the signal cable is plugged in and seated properly.  Re - plug the signal cable if 
necessary.    
l Re - boot the computer or video player.    
The monitor will not fill the entire 
screen. The picture does not fill the 
height or width of the screen. l Due to the non - standard formats of DVDs, the monitor may not show the full screen pictures. 
COMMON SYMPTOMS   WHAT YOU EXPERIENCE   POSSIBLE SOLUTIONS  
No Sound Soundbar has power  -  power 
indicator is on. l Plug the audio line - in cable into the computers audio out jack.   
l Set all Windows volume controls to their maximum.   
l Play some audio content on the computer (i.e., audio CD, or MP3).   
l Turn the volume up.   
l Clean and reseat the audio line - in plug.   
l Test the Soundbar using another audio source (i.e., portable CD player).   
Distorted Sound Computers sound card is used 
as the audio source. l Clear any obstructions between the Soundbar and the user.   
l Confirm that the audio line - in plug is completely inserted into the jack of the sound card. 
l Set all Windows volume controls to their midpoints.   
l Decrease the volume of the audio application.     
						

							   
   
Back to Contents Page   l Turn the volume down.   
l Clean and reseat the audio line - in plug.   
l Troubleshoot the computers sound card.   
l Test the Soundbar using another audio source (i.e., portable CD player).   
Distorted Sound Other audio source is used. l Clear any obstructions between the Soundbar and the user.   
l Confirm that the audio line - in plug is completely inserted into the jack of the audio source. 
l Decrease the volume of the audio source.   
l Turn the volume down.   
l Clean and reseat the audio line - in plug.   
Unbalanced Sound Output Sound from only one side of 
Soundbar l Clear any obstructions between the Soundbar and the user.   
l Confirm that the audio line - in plug is completely inserted into the jack of the sound card or audio 
source.   
l Set all Windows audio balance controls (L - R) to their midpoints.   
l Clean and reseat the audio line - in plug.   
l Troubleshoot the computers sound card.   
l Test the Soundbar using another audio source (i.e., portable CD player).   
Low Volume Volume is too low l Clear any obstructions between the Soundbar and the user.   
l Turn the volume up to its maximum level.   
l Set all Windows volume controls to their maximum.   
l Increase the volume of the audio application.   
l Test the Soundbar using another audio source (i.e., portable CD player).