Fixed-Green -square on 4K Display on Black colour

[mmbtmmbu]

Today i notice my new Asusn551VW has some problem with display.
I witness a small green square on my display when the background is pure black, the problem looks more clear when the system starts up.
i installed the latest graphic display driver, but the problem remains.
when i connect my laptop to external monitor, i don't see any green square any more.
i upload a picture focusing on the problem.
i want to know the root of problem, and could this square get larger over the time?

I upload a picture focusing on the problem.

 

[Prostar Computer]

I'm presuming that this is either your built-in screen, or the internal LCD video cable. I have not seen this specific type of display anomaly, so I cannot affirm either way whether this will worsen in time or not. You or a local technician can try reseating video cable first. One of the two components may need to be replaced.