Laptop LCD problem

Discussion in 'Offtopic Discussions' started by pengo, Dec 8, 2018 at 9:12 AM.

  1. pengo

    pengo Member

    Joined:
    Jul 14, 2011
    Messages:
    91
    Hello everyone,

    I have a laptop that has green pixel discoloration that comes and goes.

    Sometimes the pixels stay for a few days, sometimes a few hours and the LCD will return back to normal.

    I tried to search for a solution online, but only found one video on Youtube with someone experiencing the same problem.

    I am sure it is not a virus, because I have removed my hard drive and replaced with a new one but the problem persists.

    I have removed the battery from the laptop and let the laptop sit for a few hours to cool with no resolution.

    Any help is appreciated.

    Thanks,
    pengo:p&|a:

    This is the Youtube video showing very similar discoloration my laptop is displaying, but only with green pixels and not pink discoloration.

     
    Last edited: Dec 8, 2018 at 9:23 AM
    Tags:
  2. Elw3

    Elw3 ƐʍlƎ

    Joined:
    Jul 21, 2013
    Messages:
    812
    My guess: Cable broken.
     
  3. xnopasaranx

    xnopasaranx Superbad!

    Joined:
    Jan 31, 2006
    Messages:
    3,263
    this...

    can you try opening and closing the lid to see if the pattern of discoloration changes? that would confirm a connection problem.

    depending on your laptop model, you may be able to source a replacement cable, without having to buy a new panel. lots of laptop displays have a cable that can be exchanged, that is threaded through the hinge. there'll be two different cables most likely, where one carries current for the backlight and one carries the display signal (which would be the one you need to replace). if you are lucky, reseating the cable could already fix your problems, but that is unlikely the problem. you should give it a try anyway.
     
  4. hmn

    hmn Member

    Joined:
    Mar 8, 2010
    Messages:
    215
    I have a similar looking issue on my laptop (and have seen it first hand on two others). I also thought this was a broken cable at first - but it definitely is not in my case (nor is it the screen). I verified this by checking the HDMI output - the same errors were visible there as well.

    Another clue for me was that the corruption would scroll with the contents of a scrollable window - this would suggest a problem in the graphics chip or memory.

    Then again the corruption dis- and reappears when I put the screen at different angles, or just put different pressures on the case, suggesting a mechanical problem or maybe a solder joint issue on the motherboard.

    I then saw a video on YT by Louis Rossmann on "reballing" GPUs, in which he states that it is usually contacts inside the CPU/GPU chip package that go bad from thermal stress, and that resoldering would not help in that case (except for maybe the short term).

    Since the problem is manageable for me and this is an old laptop anyway, I did not investigate further, but started looking for an eventual replacement machine :)
     
  5. Eight Bit

    Eight Bit Advanced Member

    Joined:
    Nov 16, 2008
    Messages:
    1,485
    Location:
    Amsterdam, Netherlands
    I had something like this with an overheated gpu.. It was an nvida gt260m or something like that... I read somewhere that I could put the gfx card in the oven to try and "repair" it but that didn't work out obviously so I ended up buying another broken version of that laptop and repaired it with that
     
    kuru likes this.
  6. spud42

    spud42 Very Active Member

    Joined:
    Aug 22, 2009
    Messages:
    492
    Location:
    Brisbane,Australia.
    its possibly the cable but i doubt it. i think hmn has the right idea. when i worked for Compaq and the HP i replaced many motherboards and LCD screens for this sort of problem .
    hmn is right first thing to do is to see if this effect happens on an external monitor. if it does not then its the screen if it does then its a graphics problem.
    Does the laptop have a dedicated GPU? does the CPU have graphics capabilities? if you can you can also test by using the CPU graphics. this will also help to eliminate the LCD cable as an issue.
     
    xnopasaranx likes this.
  7. kuru

    kuru Irate Pyrate

    Joined:
    Jan 13, 2009
    Messages:
    1,708
    Location:
    the mockracy
    You're playing a game there. Does the laptop have nvidia graphics? If so can you set the machine to use the basic intel graphics exclusively and see if that changes anything?

    Trying output on a separate monitor as mentioned above might also help.
     
  8. pengo

    pengo Member

    Joined:
    Jul 14, 2011
    Messages:
    91
    Hello all,

    Thank you everyone for your suggestions.

    @Elw3 and @xnopasaranx You might be right about the damaged cable. So far opening and closing the lid seems to have no effect. I will open the laptop soon to examine the cable and seating.

    @Eight Bit and @spud42 You might also be correct about the overheating. I seem to recall the previous time it happened a few months ago was after heavy multitasking (like playing a game with background music). BTW, the computer is a Dell Latitude 6420.

    @kuru Yes, the laptop has nvidia. The person in the video is not me :p. It is of another person experiencing a very similar issue with pixel discoloration. I tried setting graphics to basic settings as you suggested, but the discoloration still exists.

    I connected the computer to an external monitor, but the green discoloration did not transfer over.

    After shutting down and letting the laptop sit for a while, the discoloration is now gone. I think it will return again another time. It has happened a total of 3 times this year.

    I really appreciate your help all.

    Will update the thread when the problem appears again.

    Thanks,
    pengo
     
  9. levi

    levi Still fresh, damnit!

    Joined:
    Oct 6, 2008
    Messages:
    9,948
    Location:
    Somewhere off the coast of the EU
    If the discolouration of the screen is only visible on the laptop's internal screen and not on an external screen suggests the problem is not in the GPU or its framebuffer, but somewhere after the signal for the video out diverges from the lid screen. I'd be very surprised in that case if it's not a flakey cable after all.
     
  10. xnopasaranx

    xnopasaranx Superbad!

    Joined:
    Jan 31, 2006
    Messages:
    3,263
    I am not so sure about the flakey cable anymore. external monitor showing a clean signal is an indicator that it might be something with the connection, but now that you are saying that opening and closing the lid doesn't change much and extended multitasking use is causing the effect, I'd put my money on some thermal issue, too. As I said, reseating the cable is free, so you can try that. Probably a good idea to clean the fan assembly and apply new thermal compound to the cpu and gpu. If the problem isn't permanent and you are experiencing it now for the third time this year, you might still be able to prolong your laptops life by fixing the overheating issues.

    Take the fan assembly apart! the shrouds around the fan tend to get clogged with a thick carpet like dust flap. Maybe your laptop just isn't cooling properly anymore. Have you had a look at the temperatures?

    EDIT: Or just deactivate the power eating, thermal nightmare that the nvidia gpu is and just run with the Intel HD graphics, which will give you much more battery time and less throttling. That's what I did on my thinkpad edge s430...
     
    Last edited: Dec 10, 2018 at 9:22 PM
    pengo, levi and spud42 like this.
  11. pengo

    pengo Member

    Joined:
    Jul 14, 2011
    Messages:
    91
    Thank you xnopasaranx, I will disassemble the laptop soon for cleaning. What thermal compound do you personally recommend?
     
  12. xnopasaranx

    xnopasaranx Superbad!

    Joined:
    Jan 31, 2006
    Messages:
    3,263
    I use arctic silver but it doesn't matter as long as you don't cheap out. I firmly believe, that the minor differences between the top brands are negligable.
     

Share This Page

Loading...