White bar at the bottom of the screen ( Lenovo y520 )

[JinKage]

So I bought this laptop 3-4 months ago and its been working fince until today. This white bar appears out of nowhere ,randomly (the screen flickers for 0,1 seconds, if you blink you litterally miss it) then a thin bar appears at the bottom of the laptop display and it pushes up the screen a bit. It happend twice today, both times when playing arkham knight (idk if it helps). This bar also kinda mirrors whats happening at the top of the screen as well. For example when I open chrome it mirrors the white part and it becomes a little bit bigger till I close the browser or whatever I opened. The bar has the size of taskbar so basically as big as the display. Also the bar disappears every time I restart my laptop. Is it a display problem,hardware problem or maybe just some driver or other program?

 

[dudio]

First two things I suspected was a loose connection to the screen (have you been rough with it prior to this?) or temperature.
Monitor the CPU/GPU temps with HWInfo (free) and see if that's an issue. Another thing you may try to rule out is re-installing your graphic driver.

 

[JinKage]

First two things I suspected was a loose connection to the screen (have you been rough with it prior to this?) or temperature.
Monitor the CPU/GPU temps with HWInfo (free) and see if that's an issue. Another thing you may try to rule out is re-installing your graphic driver.

Temperature while playing for my gpu is around 51. And no im not "rough" with it. I m really careful with my things

 

[Prostar Computer]

I would guess a problem with the video cable or the display adapter (whatever your GPU is). It's not something we see defective LCDs exhibit.