The presence of horizontal or vertical lines means a failing screen and/or video chip. You need to connect an external monitor. If the lines are in the monitor too, that means the video chip is failing. If the lines are only in the screen, that means that is failing.
This means you would need to have the laptop examined to see if the screen can be replaced.
We are not able, or permitted, to provide any repair estimates or equipment prices.
For this information, you would need to contact an HP Repair or Service Center.
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