Asus J1P display problem

[metalhacker]

Hello,
I have recently bought a used (and partially working) Asus J1P laptop.

Basically the problem is as follows : sometimes the display becomes as showed in the pic i took.

Here are some facts :

* Hot or cold makes no difference. It happens on first boot or while I'm using it; after 5 minutes or after 4 hours. Seems random.
* Plugging an external monitor is fine, it works ok.
* The problem will show up instantly and not gradually. It takes the LCD a fraction of a second, a blink, to turn from 100% normal to as seen in the pic.
* It shows up even on Bios.
* If the problem comes up, it won't easily go away rebooting but will eventually disappear by rebooting.
* By looking closely to the pic, you'll notice, on the right side of the LCD, 2 "bumpy" lines. Those are totally invisible when problem is not present - maybe it's info that could help.

So here's my question : is the the LCD, Video Card, Inverter, some random cable?
What could I test to actually determine what I need to replace?

I'm a computer technician so feel free to ask complex questions, I'll try and answer

Thanks for ANY help you can provide !

 

[metalhacker]

Oh, almost forgot : by trying and bending the screen, it "seems" to make no difference at all (even though the screen bezel is kinda hard...)

 

[metalhacker]

Any help?

 

[metalhacker]

Pretty pretty please? :/