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.
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July 25th, 2007 at 11:23 pm
Thanks cj2600…
July 25th, 2007 at 11:19 pm
Simon,
Sorry to hear that. You’ve replaced everything inside the display assembly and still experience the same problem? Then there has to be something wrong with the video card (integrated into the motherboard). I’ve seen many Tecra M2 and M3 notebooks with a faulty graphics card.
Even though video on the external screen is fine, it still can be a problem with the video card (motherboard).
July 25th, 2007 at 11:12 pm
Sandy,
Sounds like a problem with the LCD screen.
Just in case reseat the VGA cable on both ends.
Torque the screen a little bit and see if you can get the video back. Sometimes it helps. Do not twist the screen too much or you can crack it.
July 25th, 2007 at 11:00 pm
I have a Tecra M3 – the screen displays bright red for black (so BIOS and Windows starting screens are red). External connection works fine. I have replaced the inverter, screen, and cable (from system board to inverter and screen) from a dead M3 I tracked down, and it is still the same…
Any other ideas?
July 25th, 2007 at 10:55 pm
After a friend borrowed my laptop, I got it back and now, only the top 1/3 of the screen shows a picture. That part is perfect, but everything below it is completely black.
Is this likely the LCD or could it possibly be the vga cable?
When I hook it to an external monitor, the picture is fine.
July 13th, 2007 at 9:10 am
Joaquin,
I noticed that you posted the same question in the different thread. I posted my answer there, take a look at the comment 135.
July 13th, 2007 at 7:29 am
Hello,
One of my users has an Inspiron 6000 that is used mainly with an external monitor. Recently she came to me because the screen on the laptop had this pink hue to it, but the display on the external monitor was fine.
I started to research this and found that bad CCFL’s will cause this. However, later the same day it seems the CCFL went out all together because the screen on the laptop is very dim but you can still make out icons and wallpaper. However the external monitor display is still fine. There is no lid switch that I can see so I’m assuming it’s internal and moving the LCD display and closing/reopening does not change anything.
After reading through all the posts here I guess my question is, even though it had the pink hue which points to a CCFL issue, since it now is very dim do you think it is a CCFL issue or an inverter issue?
July 6th, 2007 at 6:16 am
Hi,
I just wanted to provide an update on my situation. Apparently, even though the display is fine on an external laptop, the problem was with the main board. A new motherboard fixed the problem and a google search showed that this is a common problem for Toshiba M4’s. Thanks for your help and I hope that this will help somebody who has this same problem.
July 4th, 2007 at 11:20 pm
Eugene,
I think these two problems could be related to each other. Maybe there is something wrong with the video cable? Try reseating the cable connectors on both ends, on the motherboard first (because it’s easier to access) and then on the LCD screen. If reseating the cable connectors will not help, try replacing the cable.
July 4th, 2007 at 12:27 am
i have an inspiron 6000. I have been having problems with my backlight working for a couple of seconds and then going dim. The only way to make the screen light up is to close the laptop and open it again but it stays lit for only 4-5 seconds.
The other issue is that the screen always has a horizontal line running across it. This line shows up from the moment the computer turns on and is booting. It can be either black or white.
It appears that a new inverter may solve the first issue but I don’t know about the second issue. Is my LCD completlely shot or is it worth changing the inverter or plugging and unplugging the connections to see if that fixes the problem.