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!
January 6th, 2012 at 1:54 pm
@ Kristens,
This looks like possible graphics card failure. Just in case test the laptop with an external monitor.
Do you see the same garbled image on the external screen? If yes, this is graphics card failure. Most likely the laptop not worth fixing.
January 5th, 2012 at 2:25 am
Whats wrong with my laptop? Same on external monitor. And sometimes doesn’t are black screen and CPU cooler are not working.
Please help!
here is the link – http://twitpic.com/7zq94y
January 4th, 2012 at 2:56 pm
@ Rusty,
Feels like a problem with the video cable. I would try replacing it first.
January 4th, 2012 at 2:54 pm
I’ve got something similar, weird coloration and flickering. I can’t get it to work from tilting the screen though.
When I bend the cable input under the keyboard I get the flickering to stop, though colour is still off.
This is a hp dv 2808, works on external display
December 26th, 2011 at 2:12 pm
@ Ramprasad,
It’s hard to tell what is wrong but if the screen light stopped working right after you dropped the laptop, most likely you damaged the backlight lamp inside the screen. It means the screen has to be replaced. This is just a guess.
December 26th, 2011 at 1:17 pm
@ waheed,
This could be one of the following:
1. Poor connection between the video cable and LCD screen or motherboard.
2. Failing video cable.
3. Failing LCD screen.
Cannot tell which one is causing the problem without testing the laptop with spare parts. Try reconnecting the video cable first.
December 24th, 2011 at 8:56 am
my laptop Compaq presario V5000 V5207TU dropped on hinges with shoulder bag, since then laptop screen not working. I can see some faint and shifted screen on lcd. it is working fine with external monitor
Please help me
December 18th, 2011 at 3:19 am
I have HP compaq, recently changed Motherboard, screen turn to red when videos are on , i have tested with external LCD it is working properly , could it be the cable problem ?
December 7th, 2011 at 6:57 pm
@ David,
If you screen looks like picture 1, this is LCD screen failure. You’ll have to replace the screen.
On some laptops you can project to the external monitor only after the laptop booted to Windows. It’s possible your laptop is like that.
Probably the LCD but cannot tell for sure without testing the laptop.
Here’s what you can try.
Disconnect laptop video cable from the motherboard and try booting with an external monitor after that. When there is no internal screen connected, the laptop should start with the external monitor. If you get external image, probably the video card is fine.
December 7th, 2011 at 6:31 pm
@ Salman,
Replace the screen.