Determining a breakdown in a laptop: a matrix or a cable?

Question

Do it yourself

Good day.
I tell you: there was a Samsung NP305V5A-S0CRU laptop.
Everything was fine, but one summer some blue-pink stripes of different transparency just formed, from the bottom of the matrix and about the height of the taskbar. I am attaching a photo.
We just formed from nothing. They didn’t drop, they didn’t beat, they didn’t flood.

For a year or more, this thing hurts the eyes. Now I'm going to deal with this problem.
I disassembled the laptop, cleaned everything, looked at the contacts from the cable to the board - everything is normal. Dismantled the monitor, removed the matrix. Found such an interesting "guest" right in the contacts. The guy is tight. How he got there is unknown.

I cleaned the contacts, looked - I did not find any external signs of damage.
I turn it on - the stripes have not disappeared.
These stripes appear immediately when turned on. Not a software problem.
If you hook up the monitor via HDMI - everything is fine on it, without any bands.
And here I have the most important question: what exactly broke? The matrix itself, or is it a train?
I'm afraid to buy a train, throwing back 1000, so that later it turns out that it's not about him.
PS: the cable itself is BA39-01134A. Matrix - LTN156AT18.

Answer 1

Matrix.

Answer 2

I think it's not one or the other, because. If the paraennium decomposed on the connector pads, then there is a high probability that it was the connector pins that oxidized and the cable in these connections "noises".
I can advise you to audit the soldering. This will not work with a simple soldering iron, you need to be able to do it.