Reason for horizontal lines in hp laptop screen

[srsurash]

Hello,
I have a HP Dv series Laptop, It shows horizontal white lines and the lines gradually increased and now a unable to see the screen even to enter log in password. will you be able to help me understand this issue..

 

[phil22]

It either needs a new screen or a new inverter board. HP laptops are unfortunately prone to hardware faults occurring.