This is so you can reminisce, and think you are watching old 8mm home movies, or by candlelight........
OH, I'M JUST KIDDING!
GENERALLY, problem is the Video Cable, or screen Inverter; in this instance.
However in reality the problem needs to be diagnosed correctly. Otherwise it will just be parts changing. Throwing money after a problem, and not wisely repairing the problem.........
Since the laptop manufacturer, and model number wasn't stated; all I can give you at present is generic information.
State the laptop manufacturer name, and model number; and I can guide you step by step in diagnosing the problem, and repairing it.
The model number can be found on the Bottom of the laptop.
Example; Acer Aspire........should be listed on top of the laptop.
5535-5030 Would be one example of model number, found on the bottom of the laptop.
For Compaq and HP laptops, look at the white Service Tag on the bottom. State the Product Number. P/N = Product Number
I would like you to start with connecting an external monitor device.
Laptop OFF, monitor OFF, connect the external monitor device to the laptop.
What external monitor device?
Dunno........laptop manufacturer, and model number wasn't stated.
It may be that you have a VGA port on the laptop.
In this case a CRT type of monitor (Looks like a small TV), can be used; or a flat LCD screen monitor if it has a VGA Cable.
HDMI or Mini-HDMI port on laptop? Then an HDTV is used as an external monitor device.
Turn the external monitor device on. If a CRT type of monitor, allow it to warm up.
Turn the laptop on.
By factory default settings, the display should show on the external monitor device. (HDTV may have to be set for this mode)
There are at least 3 display options available;
1) Internal monitor of laptop ONLY
2) Internal monitor of laptop AND external monitor device
3) External monitor device ONLY
Press, and hold down on the Fn key; and at the SAME time tap once on the Display Toggle-Over key.
This is one of the F keys at the top of the Keyboard.
F1 through F12
Acer = F5
HP and Compaq = F4
Lenovo/IBM = F8
,and so forth.
The F key generally has a monitor icon on it, (Empty rectangle with rounded corners), and a Side Arrow; on one side.
Or may be two monitor icons overlapping each other, and an arrow on one side.
This is all GENERALLY...........once I have the needed information, I can guide you step by step with this.
Display shows to be good on external monitor device, then the problem is the;
1) Video Cable
2) screen Inverter (-> IF used)
3) LCD screen
,and NOT the graphics chipset.
The Video Cable is also called the LCD cable. Depending on manufacturer, it goes by a variety of names.
The Video Cable connects to the motherboard, in an area generally under the Keyboard, or the Switch Cover.
(Switch Cover is above the Keyboard, and below the LCD screen.
Usually has the LED indicator lights in it, Power On button, and sometimes the speakers.
However, the Switch Cover can be an integral part of the Palm Rest Cover, and not a separate unit. The Power On button may be located elsewhere also. (As in the Right Hinge, for one example)
The Video Cable then routes under the left Hinge, and up into the Display Assembly.
From there the Video Cable MAY have a separate smaller cable, and this connects to one side of the screen Inverter.
This is IF, a screen Inverter is used.
The main part of the Video Cable goes on, and connects to the Back of the LCD screen.
Just one basic example of a Video Cable as used on a laptop,http://www.amazon.com/Video-Cable-Aspire-5735Z-Series/dp/B006WP5ZF2
The flat wide connector at the Top, (With the goldish Mylar plastic strip on it), connects to the Back of the LCD screen.
The flat wide Black connector at the Bottom, connects to the motherboard.
Just due to normal repeated opening, and closing of the laptop; the Video Cable may become pulled on.
This can lead to a loose connection at the Motherboard side, or a loose connection at the LCD screen side.
If a screen Inverter is used, it's cable connection may be pulled loose, also.
Due to the Video Cable may become pulled on, it can also be damaged. Stretched/Broken wires inside the Video Cable.
I'll stop here until the needed information I have asked for, has been stated in a Comment.
[No I guess I'll add a little bit.........
An LCD screen does not produce light. It needs an additional light source.
A Backlight is the additional light source.
A Backlight can be a CCFL, (Or more than one), or a series of LED lights.
(Light Emitting Diode)
A CCFL is a Cold Cathode Fluorescent Lamp. (Bulb)
Similar to Fluorescent lighting used in homes, and buinesses; but on a MUCH smaller scale.
Average thickness is 2mm, which is a little more than 1/16th of an Inch.
(Or about the width of this capital letter -> O <-)
Average length is almost as long, as the LCD screen is in height.
View the last 8 photos,http://www.laptoprepair101.com/laptop/2007/12/09/replace-laptop-backlight-ccfl-lamp/
A screen Inverter is used to convert the power (Electricity), from the laptop; for the LCD screen, and Backlight.
CCFL backlighting USES a screen Inverter.
LED backlighting MAY, or MAY NOT; use a screen Inverter.
Seems when the LED backlight technology came out, a screen Inverter was used on some models.
As the LED backlight technology progressed, no screen Inverter is used.
Just a personal observation. Do NOT write that down in stone.
A loose connection of Video Cable at motherboard, and/or at LCD screen, (And/or at screen Inverter, IF used); will cause a flickering screen.
A damaged Video Cable (Stretched/Broken wires), will also cause a flickering screen.
An LCD screen getting ready to go out, will also cause a flickering screen.
If we diagnose together, we can find what the problem is, and NOT spend money needlessly.
May just be a loose connection. Result? Just a little labor involved on your part.
May be a faulty (Bad) Video Cable. Result? $6 to $20 for a new Video Cable, and little labor, and you're back in full swing again.
May be a bad LCD screen. Cost has gone up now, labor is less.
New LCD screen may be $55 to $245. Just depends on what laptop we are talking about here.
Therefore better to spend a little labor time, or up to $20 for a Video Cable; than to spend $55 to $245, and find that was NOT the problem at all ]