black and blue lines and dots on laptop screen

[nicolem]

i have black dots all over my screen. Looks like a map and then a few smudged blue marks and lines. Just suddenly appeared. Never notice because i use a docking station most of the time. Please help

 

[mrdollarlt]

Hi,

Does lines and marks changes when you move your screen lid? If yes, then it's monitor cable fault.
Does it appear when laptop is turned on from cold start?