If our video displays aren’t operating properly, then it will be very difficult to get anything done on our computer. In this video, you’ll learn how to troubleshoot video image issues, burn-in problems, pixel problems, artifact issues, and more.
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If you’re troubleshooting a problem, where there is no video on the screen, you’ve got a completely black screen, there are a number of things you can do to help troubleshoot that issue. The first thing you should do is check to see if all of the cables are connected. And although it sounds like this is a very basic troubleshooting task, the reason we ask is that, first, it’s very easy to check the cables. It doesn’t take very long to see if they’re plugged in. And secondly, it very often is the cause of our problem.
We wouldn’t be asking if it wasn’t something that would actually solve the issue. However, if that doesn’t resolve the issue, we can move to more complex troubleshooting tasks, like checking the input for the monitor. Many monitors have different types of input. You might have an input for VGA, for HDMI for DisplayPort, and other interfaces as well. And if that input is set incorrectly, you’ll get a black screen, so check to make sure exactly which interface the computer is plugged into in the monitor, and make sure your input settings match that interface.
If the image looks a little dim and not very bright, you may want to adjust some of the controls on the front of the monitor. You probably have brightness and contrast controls on the monitor that you can use to help adjust the image. If you’re not sure if the problem is related to the monitor, or if the problem is related to the computer that you’re using, you may want to move this monitor to a known good computer. If the problem continues after moving the monitor, then you know the issue is somehow related to that monitor.
If the monitor is suddenly working, we can focus our troubleshooting efforts on the computer. If you get the normal startup messages from your BIOS and the Windows’ splash screen, but then everything goes black after that, the problem maybe related to Windows. This can sometimes occur if there are issues with the video driver, or issues with the monitor description file. In order to bypass both of those, you can press F8 during the startup process, and use VGA mode to use a basic mode configuration that nearly any monitor will be able to display.
Sometimes our display issues are complaints about the quality of the image. You may have flickering or color patterns that are not correct in the image. And this may make the entire use of the computer less than optimal.
If you’re using a VGA connector, you may want to disconnect and look at the end of that connector to make sure there are no bent pins or any pins that may be missing. If the image on the screen seems blurry or the geometry seems a little bit too narrow or too wide, you may want to look at the configuration settings in the operating system, and make sure that they match the default settings for that monitor.
You’ll want to check settings, such as the refresh rate and the resolution of your operating system settings, and compare those to what the native resolution is of the monitor. For the best possible display, you’ll want these settings to match the native resolution and settings for the monitor that you’re using. And if the image happens to be flickering on and off, you may want to also try replacing the cable and see if that resolve some of those issues.
Another configuration setting that could affect the visual display is hardware acceleration. This is often an option within the graphics card configuration settings, or within the driver itself. If you’re seeing odd patterns on the screen, you might want to try disabling hardware acceleration, and see if that resolves the issue.
As we mentioned earlier, the native resolution of an LCD display should match the resolution configuration in your operating system. If you set that resolution too low in your operating system, all of the icons and information on your screen will appear very, very large. So you may want to change those resolution settings to make everything appear a bit more normal on the screen.
Another problem you often see on many different kinds of monitors is burn-in. When an image is constantly displayed on a screen, you’ll find that that screen will lock that image in place. And even when that image is not being displayed anymore, we can still see at least part of that image still on the display.
Here’s an example of some burn-in, or ghosting, that you might see on a display that’s from an airport. This is showing all of the available flights you can see there are flight numbers and gates and times. And it shows if the flight is on time, or what the scheduled time might be. You can see that this on-time marker used to be a little further to the right, because you can see this discoloration on the screen. And you can clearly read, on time, where this image has been burned into this display.
Many modern displays will recognize when an image has been displayed on a screen for an extended period of time. And if that occurs, it will begin to move the image one pixel or two in a different direction to try to make sure that the image is moving around and not burning in any part of that screen. Certain LCD displays might even have a pixel that is stuck to a particular color that may have been left on for an extended period of time. If that occurs, you can sometimes remove that from the screen by displaying a white screen over an extended period.
If a display has a particular pixel that is always showing a color, we call that a stuck pixel, where it is constantly bright. Even if the entire screen is black, you will still see that brightly lit pixel on the screen. You have also pixels that aren’t working at all. We call these dead pixels, because they will never show any particular color. They will always be black on the screen.
If you have a stuck pixel or a dead pixel, this is usually related to a problem with the display itself. And to be able to resolve that, you would need to replace the LCD display.
Artifacts are odd images or strange graphics that are appearing on the screen. And we can sometimes resolve this by looking at the configuration of the graphics card itself. There maybe options there to enable or disable things, like hardware acceleration. And that might resolve those unusual graphics.
Another problem you might find is image persistence, where you might close a window on the screen, and yet part of that window is still being displayed. That information should be refreshed, so usually changing the configuration of your graphics card or resetting the monitor might resolve that issue.
And if you’re seeing motion trails when you move your mouse around the screen, that may indicate an issue with the graphics card. You might want to disable any advanced features on your graphics card to see if that resolves those motion trails.
And if you have an external graphics card in your computer, it maybe a very large card like this one that puts out a lot of heat. Many of these graphics cards have their own heat sinks and fans in order to keep these cards cool. But if these are not cooling your system properly, you might get blue screens of death or the system may shut down abruptly due to overheating.
To resolve this, make sure you have the latest video drivers and the utilities necessary to monitor the temperature that’s on this card. You might also want to monitor the internal temperature of your entire computer to see exactly where the hotspots might be, and where you maybe able to improve the cooling of your system.
Category: CompTIA A+ 220-1001