Horizontal Lines on LG 34GK950G Monitor

Hello!

I'm reaching out for help with my LG 34GK950G monitor. Recently, I've noticed horizontal lines appearing on the screen. Sometimes these lines disappear briefly, but they often come back and can become more pronounced.

The lines are visible even when no cables are connected, except for the power supply (e.g., i see the lines in the monitor's menu).

In the past, I had to get the screen repaired when it stopped displaying anything at all. This time, I would like to try repairing it myself. I'm looking for ideas on what I can diagnose to find a solution.

I have already tried replacing the power supply block with one that has the same specifications as the original, but unfortunately, it didn't make a difference.

Any suggestions or guidance would be greatly appreciated!

Thank you.

Here is a link to pictures of the problem: https://photos.app.goo.gl/aAC8spvbSKt8jR...

Update (2024-07-07) :

I spent a good part of my day yesterday running multiple tests (and I updated the Google Drive link with some more photos/videos), but unfortunately, it feels like I didn't achieve much. Here are the key points:

I tried disconnecting the connectors (drivers? the white ones in the images, labeled 1 and 2), one by one, to see if the lines would disappear from one side or the other of the screen. It seemed that when I disconnected connector 1, the lines disappeared although the signal was unstable (see the file 20240706_094621).

I also tested the brown connectors (the two that connect two boards) and again, it seemed that when I disconnected the connector on side 1, the lines were less present. But again, it's hard to say as I have no experience with this type of repair and the signal is inherently unstable once these connectors are removed.

I gently tried touching the connectors that are attached to the panel (at the bottom), without noticing any differences.

I decided to do some online research and came across FrugalRepair's videos (see https://www.youtube.com/watch?v=SbGAkRga...) which I found very interesting. I wanted to apply the "tape hack" but couldn't figure out where the connectors that manage pixel polarization are located (thinking that the horizontal lines might be caused by this).

I'm not sure replacing the main board will fix the issue. I'm considering selling the device for parts unless someone has an idea of what else I can try.

Please note that I forgot to mention another issue the screen has had since it was first repaired: if the screen loses power completely, after a few hours, it takes increasingly longer to turn on. For example, if I unplug it for 24 hours, it might take several hours before it turns on again. I have added videos showing this (20240706_111624.mp4 and 20240706_121544.mp4). I suspect a faulty resistor (which only works after heating up sufficiently). I'm not sure if this is related to the horizontal lines problem, but in the interest of transparency, I wanted to correct my oversight.