display - What is the cause of a vertical white line on an LCD monitor?

07
2014-07
  • Deviruchi D Devourer

    This just happened yesterday when I was browsing the internet. My AOC N941Sw monitor is suddenly showing a thin horizontal white line near the center of the screen. The white line distorts the images. I tried checking the cables for loose connection and dust particles but the white line is still here.

    There are times the entire image below the horizontal white line flickers and move up and down. When this happens, I just turn off the monitor then the flicker goes away but the white horizontal line is still there. After a few minutes, the same thing happen all over again. Is there a way to fix this?

    • Answers
  • Mario

    Sounds like a hardware issue with the monitor (or more specific, the built in LCD panel; in short: time to buy a new one).

    Due to the fact that the issue is isolated to a single line (even with multiple pixels in height) it's unlikely it's the actual signal (e.g. cable or connector pins).

    Some issue with the connection would most likely screw up several lines and/or the whole image and it won't be isolated to exactly one line (especially with digital connections).

    In a similar way, issues with the graphics card should most likely cause issues with the whole screen (like garbage/random patterns). Those shouldn't be isolated to a single line.

    This could be some extreme case of stuck/dead pixels (i.e. the whole row is somehow damaged).

    What you could try (this won't necessarily help because we simply don't know what caused the actual issue in the first place):

    Turn off the monitor, disconnect all cables, and put it flat on your table (screen up) so it's sitting plane on the table. Let it sit there for a night, then try again.

    If everything else fails, what happens if you use your finger nail and pull it over the faulty line? Don't push too hard, just so there's some pressure (typically shows some short colored trail that should disappear within 1-2 seconds). Can you see any additional patterns or "waves" that don't fit to what you see in other areas of the screen?


    • Related Question

    display - Artifacts on LCD monitor?
  • lc.

    I have an LCD monitor which was, arguably, relatively cheap. Undoubtedly it's due to cheap manufacturing, but after a while of continuous use, I start to see artifacts of previous images (resembling CRT burn-in). I've also noticed the these areas of the screen tend to get a bit toastier than unaffected areas.

    Turning off the monitor for a while does return it to normal, so it's not a permanent problem, but it is rather ugly when it happens. A Google search resulted in no more than "this happens sometimes". Does anyone else have experience with this?

    1. Anyone know the cause of this? (Feel free to get as technical as you'd like.)

    2. Aside from the obvious of trying to exercise the pixels as much as possible when in use (i.e. don't leave SO/SF/SU in a browser open all day), is there anything I can do to reduce this? Would improving cooling help or is it not heat-related?

    I don't think it's cable or video card related at all. It's usually the top left corner, and artifacts of things that don't change regularly (the desktop, browser toolbar, etc) are still visible when I change what is shown there (usually by switching to another application). Like I said, it looks like CRT burn-in. When the monitor is off for a while and is turned back on, however, the problem goes away.


    • Related Answers
  • joe

    It could very well be the cables, but where are the artifacts located on the screen? That is a huge determinant. The edges of a screen are generally warmer and so it may not be a related symptom.

    But that aside, the answer you're looking for has many possibilities. My belief is simply that you have dying/near dead pixels.

  • user1232

    I've had some success in this area both with switching to a better VGA cable and with switching to a DVI cable instead, if the monitor supports DVI. Of course, you may need to buy a video card that supports DVI, but those are much less expensive than a new monitor.

  • dyve

    How is your monitor hooked up? If you are using VGA cable now, but have the option to go DVI, try to see if switching to DVI gives you a better image.

  • David Snyder

    I have no idea the cause, but both of my dell 2005FPWs exhibit this. They're both in use 12+ hours a day, some times displaying the exact same image (iTunes). I didn't get any farther than you, except to discover that IPS-based models are somewhat more susceptible. It certainly is not a cabling issue, as I've had the same cables over the 4+ year lifespan of the monitors which have only started having the issue in the last year or so.

  • Free Wildebeest

    I had similar sounding symptoms with a cheap TFT that I had. I managed to work out that it seemed to be related to the monitor getting too hot. If it's somewhere with bad airflow or in direct sunlight I'd suggest moving it and seeing if that helps it.

    Or try turning up your air conditioning if you have it.