Dell Inspiron 5406 2-in-1 — Screen Developing Horizontal Lines (Hardware Issue Diagnosis & Solution)

Hi everyone,

I noticed a thin black horizontal line at the very top of my screen. Over time, additional lines appeared next to it, gradually merging into a thicker black band. Later, the bottom of the screen also started developing similar lines. The frequency of new lines increased, and now both the top and bottom of my screen have visible horizontal line bands.

I confirmed it’s not a software issue, because these lines are visible even in the BIOS screen.