Display problems on laptop

[Yohelpmedogimlost]

My old laptop has a problem, when on battery power the backlight is so dim that it's barely visible at night in a dark room.

When plugged in it has some white horizontal stripes on top (~1cm in total)

 

The stripes occurred after I changed the thermal paste, but they usually disappear after pressing the lower right corner of the screen. The backlight problem occurred later

[doomsriker]

On 10/15/2019 at 12:44 AM, MariusIonasco said:

My old laptop has a problem, when on battery power the backlight is so dim that it's barely visible at night in a dark room.

When plugged in it has some white horizontal stripes on top (~1cm in total)

 

The stripes occurred after I changed the thermal paste, but they usually disappear after pressing the lower right corner of the screen. The backlight problem occurred later

Sounds to me like you might have messed up your display’s ribbon cable on re-assembly. You can often find replacement screens or cables on eBay cheapish.