How to troubleshoot Dell Monitor Issue?

Asked By 140 points N/A Posted on -

My old monitor was busted already. When my uncle heard about this, he gave me his old but still working Dell flat panel monitor as he was able to buy a new one already.

When I first connected it in my HP 6750 CPU, it worked fine. The next day I used it, I noticed a discoloration first, before it displayed disrupted image until it became black and white lines. These lines are moving from top to bottom endlessly. I checked the physical connections of the cables, and all are fine.

When I tried to restart the computer, everything will work for ten minutes, but after that, same scenario will happen. I restarted again, checked device manager for my monitor and adapter, and it seemed fine. I think my brother installed two video cards, I am not just sure. I want to know if there are other options I can try to fix this before I check the insides of my CPU.

Best Answer by Peter Morales
Best Answer
Best Answer
Answered By 5 points N/A #108506

How to troubleshoot Dell Monitor Issue?


Hello Bill,

Too bad to hear that you are having monitor problems that cannot be ignored, since the monitor allows you to view your desktop and is currently unavailable due to the symptoms you described. I have been working as a computer hardware tech for almost a decade now and quite familiar with problems associated with your monitor.

To properly diagnose your monitor problem we have to do a few checks first to confirm that every device on your computer setup works as it was intended to be.

  • As a preliminary, we have to make sure which part of the system the problem is coming from. Is it the monitor or the tower containing the CPU, motherboard and other peripherals? Is it a VGA connector gone loose problem? Do the diagnostic checks by:
  • Unplugging and replugging the VGA/DVI cable connectors from monitor to CPU. Check for loose joints, screw if necessary. Do the same for video cards that may have been unseated and gone loose. Remove from PCI slot, clean contacts and reinsert when done.
  • Facilitate a real time test by borrowing a known good monitor from a friend and trying it out on your rig. See if it creates the same symptoms. Confirm your findings. Is it the monitor or the CPU rig? If it’s coming from the CPU, do the video card slot checks, or in your case which has a dual card setup, try it out on each port, connecting one at a time and noting the results. Now if a monitor is unavailable, you can test your own monitor using another CPU, or on an external display setup using a laptop. Note the results as well.
  • Remove any magnetic influences nearby which might cause some problems on your monitor, noting the “discoloration” you previously mentioned. This more or less affects monitors using CRT (Cathode Ray Tube) technology. It sort of distorts the images on the monitor because magnetism affects the yoke connected around the CRT, disrupting the scanning lines.
  • The constantly moving “black and white” lines from top to bottom may mean one of two things. It may be what they call a “retrace” line, which has completely blanked out the image with a thin white line moving from top to bottom. It is caused by a faulty RGB circuit board located at the neck of the CRT mentioned earlier. The screen brightness circuit has lost control of the brightness setting, causing the lines to appear. Another might be the individual Red, Green, and Blue controls that have malfunctioned as a result of ageing.
  • Another similar cause for modern day monitors is a faulty power supply module that has blown capacitors, causing unfiltered voltage fluctuations to manifest on your screen. They can be returned to normal state once replaced. The power supply module itself has a “repair” or “replace” option if the opportunity presents itself.
  • In cases where the power supply checks OK, it could be a video drive circuit error on the monitor itself that causes image distortion when warm enough. The circuit is replaceable by any service center that repairs computer monitors.
  • On the software side, it would not do any harm if you do the usual checks for updated video card drivers and proper video resolution settings. They may or may not have any effect, depending on the software configuration you have.

You see, it is just a case of properly identifying which is malfunctioning, and in your case it is either the monitor, or your CPU rig. From there, you should have gathered by now which needs further attention. 

Answered By 0 points N/A #108507

How to troubleshoot Dell Monitor Issue?


Hi Bill,

I hope this ways to can your fix computer monitor/display/adapter

Monitor problems are some of the most common computer problems since the voltages inside a monitor can be as high as 10 KV. Many of the problems can be fixed yourself by simply changing the settings but in a few cases you may have to either replace or repair the monitor.

How to troubleshoot and fix computer monitor/display problems

1. The monitor/display flickers
Check the refresh rate. If the refresh rate is 50 Hz/ 60Hz (depending on which country you stay), it can be affected by interference from electrical power signals like those from fluorescent lamps . Increasing the refresh rate to 72Hz is recommended , since higher refresh rates reduce eyestrain and headaches

2. The display works fine initially, then after some time there are black lines on the screen and then the display disappears

There is a problem with the copper windings in the CRT monitor which are getting heated. It is better to replace the monitor

3. For a new monitor, you get a blank screen or distorted image.

Many monitors, especially LCD monitors, can only handle resolutions which are less than the native resolution, so set the resolution at the native resolution only. The native resolution of a LCD display is lower for smaller LCD screen sizes, typically 1024 X 768 for 15" LCD. CRT monitors have a better resolution than LCD displays

4. The display on the monitor is not steady

This is a result of power system interference from users of the power grid, particularly UPS, power tools and heavy machinery. Try changing the position of the monitor.

5. There is a shadow on the images on the display

Try reducing the contrast setting on your monitor.

6. Monitor becomes blank occasionally

 Could be a problem with the display card, check with another monitor. The monitor display cord and power cable should be fixed properly and there should be no loose connection.

7. Dark Spots on the Screen.

Move speakers and other magnetic devices away from the monitor.

8. Incorrect Colors – red may become dark brown, blue becomes purple.

Check your video cables and connectors for bent or broken pins and wires. Sometimes there may be a problem with your display card, which can be returned using a software

Answered By 590495 points N/A #327882

How to troubleshoot Dell Monitor Issue?


Even if your CPU has two video cards installed it shouldn’t be a problem. If you see lines moving from top to bottom, the problem there is usually with the monitor. Try connecting the monitor to another CPU then see if the problem follows. If the problem is the same then you need to replace your monitor with a new one.

But if the monitor worked fine on the other CPU then that means the problem is with your computer. In this case, try updating your video card driver. See the following list of manufacturers and download the latest video card driver:

If this doesn’t work, try reseating the video card. Turn off your CPU then open the CPU case. Remove the video card from the slot. Now, get a pencil eraser and rub it on the gold contact pins of the video card. Do it on both sides. When you are finished, wipe it off with a dry clean cloth and insert it back to the slot.

Related Questions