Laptop screen flickering and freezing

[Walking Talking Potong Stim]

There's a white line which comes and goes. And with the coming and going of the line, the whole screen moves up and down 1 mm or so. And some days, it seems to freeze completely when the line isn't there.
Computer is HP Probook 4540s. Screen refresh rate is 60 hz. The other only option is 40 Hz wich makes it flicker like crazy.

[rotNdude]

Try hooking up an external monitor to see if it does the same thing.

[Walking Talking Potong Stim]

I'll definitely have to try it. The lines aren't caught in screenshots.

[Walking Talking Potong Stim]

Okay, extra delay, but External monitor runs perfectly. No lines, no frickering, no freezing

[Seven7]

if the laptop lid (screen) to open and close - whether it affects the image?
If yes - you need to change the trail, the wire broken on the left hinge area

if the warranty is over, get instructions for the service technician how to disassemble the laptop, find the part number of cable, and buy it

[Walking Talking Potong Stim]

Nope, it doesn't affect the image when I move the lid. It's pretty obvious there's something wrong with the screen itself only, but what else can I do except taking it to a service station for now?

[rojimboo]

If you know what you are doing, or are confident after some Youtube videos, check the GPU cable to the mobo and the display cable.

Sometimes they become loose.

[Seven7]

if you can't replace display panel (or driver) - use external display. no other ways

btw replacing assembled laptop LCD panel - the easiest type of repair that is possible to perform yourself, you need only purchase the same exact part, then do not have to configure anything, do not need a soldering iron, engineering codes and modified firmware

[Walking Talking Potong Stim]

Hm okay, so I simply need to replace the display panel, or rush to the service station. I'm not really a DIY expert, so I'll try the service station first. Thanks for all the help

[Seven7]

if a repair man have the required part already, he replace it for 10-15 minutes, or call back when find or order a suitable part
and it will be more accurate diagnosis and final
+ can be replaced thermal paste - the thermal paste, which are sold at retail, is much worse than the one, used in service workshops, first dries quickly...