Here is a simple diagram that will help you to understand how a notebook display assembly works and how an image appears on the screen. I’m not an artist and I tried my best drawing this diagram, so if you cannot see a laptop in this picture, don’t be mad. 
A generic display assembly includes a very few parts and knowing them will help you to understand witch part can cause a problem if you laptop video not working properly.
Video cable. A video signal from the motherboard goes to the LCD screen through the video cable. The video cable connects to the motherboard (or video card) through the connector 1. The video cable connects to the LCD screen through the connector 2. The video cable (in most cases) is also responsible for supplying a necessary voltage for the FL inverter board. The video cable connects to the FL inverter board at the point 3.
FL inverter board. This board is responsible for converting low voltage DC power (point 3) to high voltage AC (point 4), necessary to light up the backlight bulb. If the FL inverter board is bad, the LCD screen (backlight bulb) will not light up when you turn on the laptop, but you still should be able to see a very dim image on the screen.
Looking for a new screen, video cable or inverter board? Find it here.
CCFL (backlight bulb). When the backlight bulb lights up, you can see an images on the LCD screen. In most cases the backlight bulb is a part of the LCD screen and if it’s bad, the entire screen has to be replaced. By the way, some specialized repair shops can replace the backlight bulb itself.
Lid close switch. The lid close switch is a small button that locates close to the display hinges. On some newer models there is no button, because the switch is magnetic. You can set up your laptop to go to a hibernation mode or to a standby mode when the LCD is closed. It’s done through power management software. These modes are triggered when the display is closed and the lid close switch is pressed down. If the LCD screen on your laptop will not light up when you open the display assembly, check the lid close switch is stuck inside (it might happen because the switch is dirty).
Related articles:
Fixing notebook video problems.
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March 15th, 2012 at 2:14 pm
@ yad,
I have no idea what it means.
March 15th, 2012 at 8:26 am
My Asus laptop has only show asus logy only. It can’t go ahead(not to going on bios also). I called to technician he said me it must to copy bios. What’s it means ? How to copy it? Asus k42m laptop model.
January 8th, 2012 at 10:30 am
@ Ali,
Why did you disassemble the laptop? What was the problem?
Did you disconnect the inverter while the laptop was running?
January 8th, 2012 at 2:53 am
i have an LG RD510 and when i was dissembling ,i remove “4″ (the FL inverter board from the CCFL (backlight bulb)) while the laptop is working and the screen is on ,i return it to his normal place but the screen wont work ,help me plz i can’t find i solution , i tried to restart the laptop but in vain.
December 27th, 2011 at 10:56 am
@ venkatesh,
First, check your laptop with an external monitor. Make sure the external video works properly.
If the laptop image jumping, the problem could be with one of the following:
1. Bad connection between the video cable and LCD screen or motherboard.
2. Failed video cable.
3. Failed LCD screen.
I cannot tell which one is causing the problem without testing the laptop with spare parts.
Try reseating the video cable connectors first. If it doesn’t help, most likely this is LCD screen problem. If replacing the LCD screen doesn’t help, try replacing the video cable.
December 27th, 2011 at 6:29 am
its a dell studio 1537 laptop
how shoul i proceed next with my laptop for this problem of screen jumping
December 26th, 2011 at 2:08 pm
@ demondriver123,
When you turn on the laptop, there should be LG logo before Windows starts loading.
Is this logo shifted too or it appears correctly, right in the middle of the screen?
December 26th, 2011 at 2:01 pm
@ Murray,
No video, no light on the screen at all? This could be the video cable related issue.
1. Test your laptop with an external monitor and confirm that external image works good.
2. Check connection between the video cable and motherboard. It’s possible the cable just got disconnected.
December 24th, 2011 at 3:47 am
hi my laptop monitor display screen problem is like this!! help!! below is the picture. there’s a black panel on the right screen and multiple image below? how to resolve this probelm?! anyone help me! im using LG notebook X130 model.
http://www.flickr.com/photos/7...../lightbox/
December 23rd, 2011 at 5:07 am
Hi,
I have a HP compaq nc6720.
Laptop turns on, sounds okay, desktop opening, so motherboard works fine, i hear the every sound.
But monitor does not work, no display, no reactions, no any light on it. Looks like there is no any electricity or no connection from motherboard.
It has began since i tried to input another adapter before 3 days.
i need your help immediately, thanks so much..