A vertical white line appears on my screen - Acer Aspire 4315 Notebook

This problem can be caused by a lose connection between LCD and motherboard, however you can check it by opening the LCD or hinge bezel to ensure if there isn't any lose connection.

Somebody dropped it

If you wish to get some details; visit the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/
Line faults & possible causes to LCD & Plasma screen are given with illustrations. You can get an idea about the fault to an extent. Faults to all LCD & Plasma screen are similar, irrespective of its brand and screen size.

That answer I agree makes no sense.

Most of these sets have NO vertical hold and if did it will not cause the lines.

A brief educated guess:

Set has a main board that communicates and controls the screen--tests for that are not simple (checking waveforms with a scope and signal generator).

The model indicated here is a DLP that uses a lamp (let me know if model listed is not the one you have).

In DLP sets aside from main/digital board you also have a optical light engine---it processes all signal in and out to the screen.

Optical engines do fail and cause some simple and some complicated picture issues.

Some will even cause the set to "lock up" with a picture or strange looking screen---clue to this is you have to shut the set off by pulling the power cord.

The set may be old enough they do not really want to help you or even talk about it.

You have a failure in the vertical circuit. Service can run between $75 to $150 depending on your area.(In home repair will cost more) If set is older then 3 years and under 27" recommend replacing it.

This could be a poor connection with the LVDS cable which runs from the main video processing board to the screen, or a fault within the video processor on the main board. Worst case scenario is it could be a fault with the screen itself.

It's the Electrolyte Capacitor ( Elco )on the Vertical board that already damaged, try replace it with new ones.

Connect an external monitor to your laptop. If the problem appears only on the display of the laptop and not on the external monitor in the same time that means the video card is ok and the problem could be : the screen of the laptop or the invertor or the cable that attaches the screen to the mainboard. Have it checked by a professional.

problem in vertical section.

1. Solder the vertical ic

2. vertical ic supply capacitor problen.

3. dry points in neck board.

It is the problem of monitor pcb in vertical section.check vertical ic for dry soldring. Resolder the ic if problem still on then change ic or check components related ith it. check continuity of vertical deflection coil.
Hope this be of initial help/idea. Pls post back as requested, how things turned up or should you need additional information.
Good luck and kind regards.
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