My laptop only shows lilane stripes?

It is so:

Lilane stripes appear every few seconds on my laptop and you can't see anything. Why is that?

I would like to add a screenshot here in the question, but of course my laptop does not pick up the stripes.

The graphics card or the screen or the connection cable could be defective

The graphic artist is drunk.

Put that thing back, could work.

Why do not you take a picture with your smartphone?

Either your graphics card is in the bucket (buy new) or the video driver has shot it (reinstall) or the monitor cable has a wobble (check cables and contacts) or the screen is in the bucket.

Unfortunately, the warranty is already over: - /

Do not return, reset, de-energize and then restart.

That's how it looks!