Here I’m going to post some laptop screen photos showing bad video output. I’ll explain what was wrong with the screen and how I fixed it. I plan to ad more examples as soon as I get new pictures. If you have your own example (and know how to fix it) please let me know and I’ll post it too.
Here’s some help for finding a correct part for your laptop.
Other post related to troubleshooting laptop video problems:
How to troubleshoot and fix laptop video problems
Taking apart notebook LCD screen
Replacing LCD screen inverter
The newly installed screen is not working
Example 1.
Here’s a picture of Satellite M55 LCD screen I made this morning. I got this video output as soon as I started the laptop. There were a lot of vertical lines, and they were changing color without any pattern. To me it looked like Northern Lights (never seen in real life) 
. The external monitor worked fine.
As soon as I applied some tension to the screen it changed the pattern. Some horizontal lines appeared in the middle of the LCD.
Here’s the difference. When I torque the screen, the image appears but it’s distorted with some horizontal lines running across the screen.
Reseating the video cable didn’t make any change and the problem was fixed after I replaced the LCD screen.
Example 2.
I took this picture from Toshiba Satellite M65. I think that this example is very typical. One day you wake up, turn on the laptop and see one or a few hair-like vertical lines in different colors.
When you move the LCD screen some lines might disappear or more lines appear on the screen. A video output on an external screen would be perfect, without any lines. Unfortunately, these lines indicate a screen problem. I’ve never seen this kind of video output caused by a bad video cable or bad FL inverter board. My laptop was fixed after I replaced the LCD screen.
Example 3.
The photo below comes from Toshiba Satellite 5205. The laptop displays identical vertical lines all over the LCD screen as soon as I turn it on. Sometimes these lines are red, sometimes they are blue, sometimes they become wider and change color to white.
The same pattern appears on the external monitor. It displays same vertical lines. When the same video defect appears on both monitors – internal LCD screen and external screen, then most likely it happens because of a bad video card. On some laptops the video card is integrated into the system board, on other models it’s a separate module.
In this example, the vertical lines were caused by a failed video memory on the system board. I’ve tested the video memory with Microscope utility and it failed the test. In Toshiba Satellite 5205 the video memory is integrated into the system board. To fix the problem, I’ll have to replace the board. (We do not have equipment to replace the memory module itself).
Example 4.
Here’s another example of a bad LCD screen. My bad! It wasn’t the LCD screen problem.
As soon as I turned on the laptop, I was getting these reddish marks on the LCD screen but not on the external monitor. Reseating and replacing the video cable didn’t help. The problem disappeared when I installed my test LCD screen. Yes, for some reason I wasn’t able to reproduce the problem on my test LCD screen. But the reddish video appeared again as soon as I replaced the screen. I guess it happened because the system board had some kind of intermittent problem with onboard video or video connector. Long story short, I had to replace the system board and it fixed the problem. Yep, I misdiagnosed this laptop.
Example 5.
Here’s one more example of a faulty LCD screen. The left half of the screen works just fine but the right side is completely white.
Example 6.
Here’s another laptop with a bad LCD screen. This time it’s a tablet PC.
Example 7.
This screen looks like the screen on the example 1. I hooked up an external monitor and the external video works perfectly fine.
Here’s the difference. When I torque the screen, the image appears but it’s distorted with some horizontal lines running across the screen.
After a few seconds the image washes away.
I had to replace the LCD screen.
Example 8.
This laptop displays inverted colors right from the startup. As you see, the Toshiba logo is light green instead of red. The background is light gray instead of black. The Intel logo should be blue on a white background but it is red on a black background.
When your laptop displays inverted colors as on the picture above, this is an indication of a bad screen. You’ll have to replace the screen.
Example 9.
Here are two more screens. In both cases this problem is related to the LCD screen, witch means the screen has to be replaced.
On the image below you see a white band running from the top of the screen to the bottom. This band appears right from the laptop startup and runs through the logo too.
On the following image only the left side of the screen is working properly. This problem is caused by faulty LCD screen.
Are you looking for a new LCD screen for your laptop? Try here.
If you find this article useful, please consider making a donation to the author. Thank you!
February 2nd, 2012 at 8:36 am
@ Anna K,
Connect an external monitor to the laptop and test external video. If external image is OK I assume this is not a problem with the motherboard.
You can try reseating the video cable on the back of the screen. Maybe it got loose. If reseating the cable doesn’t help, probably you’ll have to replace the screen. Most likely it got damaged.
February 2nd, 2012 at 8:29 am
@ Tom Dicuirci,
First of all I would test the laptop with an external monitor. Can you get normal image on the external screen or it also has lines?
January 26th, 2012 at 3:37 pm
Hi I’m quite glad to have stumbled upon this article because I’m currently having an issue. I turned on my IBM Thinkpad T43 laptop after it had a small fall (in my opinion at least) and it had all those funny northern lights lines like your first picture. However when I touch the screen I don’t have an outline of an image or anything. Is there other way to fix the screen without having to replace it entirely?
January 26th, 2012 at 11:36 am
When I turn the laptop on The normal boot windows seqence never happens on the screen. But you can just barely see on the top of the screen something that resembles window not booting. This is all hard to see through the verticle and horizontal lines. I tried torqing the screen with no change. I tried running a windows 7 boot disk but there is no reponse.
January 24th, 2012 at 12:52 pm
@ Tom Dicuirci,
I don’t remember if you can switch Compaq Presario CQ50 laptop to the external monitor unless it’s booted Windows OS.
For proper diagnostics, it might be necessary to unplug the video cable from the motherboard and try turning it on with an external monitor after that.
Just in case, here’s Compaq Presario CQ50 laptop disassembly guide:
http://www.insidemylaptop.com/.....70-laptop/
The video cable connector on the motherboard shown in the step 10.
What happens when you turn on the laptop? Can you see normal hard drive activity at all? Maybe you can hear Windows boot sound?
What if you torque the screen a little bit, does it change image at all?
January 24th, 2012 at 8:16 am
My CQ50 laptop Lcd screen shows shows horizontal and verticle lines only. My external monitor output plug sends no signal
January 20th, 2012 at 11:51 pm
KK,
Connect your laptop to an external monitor. Change the video output to the external monitor and start watching videos. Does external video has same problem?
If the same problem appears on both screens, the internal laptop screen and external monitor, most likely this is graphics card related failure.
Try cleaning the heatsink and cooling fan. Maybe it happens because of overheating.
If cleaning the laptop doesn’t help, I think the graphics card is going bad.
January 20th, 2012 at 6:57 pm
@ Karen,
First, I would test the laptop with an external monitor. Can you get image on the external monitor?
January 18th, 2012 at 10:21 pm
The display of my laptop has a problem. When I play any video, patches appear on the screen and the quality of video is very bad. But the images do not have any problem. Only videos. Let me know what the problem is and how to fix it.
thanks, KK
January 15th, 2012 at 6:54 pm
What can you do if the laptop LCD screen turned completely white?