How to fix Flickering dell latitude 2120 netbook screen

SOURCE: dell laptop screen goes blank when ac adapter plugged in

I believe I have found the problem with the 1525 that I am currently working on which has the same problem that you describe. Ultimately I think it's a problem with the inverter in the LCD. When the laptop is powered by battery the brightness is lower than full. When I plug in the power adapter the brightness goes to "full" and I hear a faint sizzle and the LCD's backlight goes off. Same as if you hold the Fn key and press the up arrow to brighten it, it will do the same thing when you reach near the full brightness. So for now I have fixed this problem by going in the Power Options and clicked on Adjust the display brightness on the left. Slide the slider to the left on the "plugged in" part and now when you plug it in it shouldn't make it go blank. I do want to note that I hear a faint buzz coming from the LCD when I plug it in. That must mean the inverter is faulty. WAY TO GO DELL!!!!!!

SOURCE: Dell Inspiron 1501 screen half black

Had the same problem. Fixed it though. Here's how:
You'll notice that the screen comes back to life if you press down on the very top of the green line. This is because a controller circuit board behind the LCD screen (at the top) is pressure fit flat-surface-to-flat surface to the contacts on the back of the LCD. Eventually, the sticky substance that holds this circuit board in place wears thin, collects dust, etc.. and the connection between the circuit board and the lcd contact is lost. The line appears where this break in contact has occured. 
So, the solution is to increase the pressure at that point to reestablish the connection. I wasn't able to remove the circuit board to clean beneath it as it seemed too likely to cause damage. Nor would I have had the right adhesive to connect it back, so I simply removed the LCD and put a bunch of tape at that point so that it would "push" with a little more pressure when screwed back into place. Worked great.
To remove the LCD, pull off the 6 feet around the screen. Remove the screws behind them. Carefully pry off bezel with a small flathead screwdriver working your way around it. Once removed there are simply 4 screws on the left and 4 more on the right of the LCD to remove. Pull out screen carefully and start stacking bits of tape on the spot where pressure seems to work best. Put it back in and see if you've made any difference. I did this with the computer on so I could verify my results. Just be careful not to short out any naked contacts.
If this doesn't work for you, at least you'll know you just need to replace the LCD, not the video card. Easily found on ebay.

SOURCE: IBM Thinkpad screen flickers

Good afternoon!
From what you've described, I'd suspect that the video chip is starting to separate from the mother board. This is not an uncommon happening with the T41s. In fact, I have personally had it happen to me. So much for the sad story, but what do we do about it?

First, we do some diagnostics to verify that this is the problem. The next time this happens, try pressing down on the following location of the keyboard area. Place two fingers of your left hand on the keyboard cover, just below the left end of the space bar and and to the left of the red and blue mouse buttons. Firmly press down and see if it will start working again. If that doesn't work, try placing the thumb of your left hand in the area that you placed your fingers. With the fingers of your left hand, reach around and firmly lift the lower left hand corner of the laptop a little bit (maybe 1/8 to 1/4 inch). This will flex the motherboard and can cause the video chip to properly contact the motherboard.

If this works, you have pretty much verified that this is the problem. Also, if this seems to work, get back to me for a possible short term fix and what needs to be done to fix it permanently.

One other word of advice, if you haven't done it yet. Back up everything that you need to save, just in case.

Will be waiting to hear from you and have yourself a super day!
Ron-

SOURCE: Dell Latitude D800 Boot Problem

Did the diagnostics pass the RAM and the hard drive.
You should check the BIOS settings to see if the hard disk is detected, if possible reset the BIOS back to the default settings and see if the computer boots up.
If not :-
Then it appears that the operating system is either corrupted or system files were deleted or infected with viruses.
Your only option is to do a operating system repair or a complete new install of Windows.
I recommend you do a new install.

SOURCE: black screen on dell latitude d630

Seems it is the screen which has gone bad. get your screen replaced