This problem is related to the LCD-Motherboard connector. It is either damaged, or not connected properly or the contact is loose. Because of that, some portions of the screen doesn't receive the proper video signal. You will need to take the laptop to a service center to have it dissasembled and checked for either of these problems. It shouldn't be an expensive repair, unless the connector itself is damaged. If so, they will charge you for another LCD display if they don't have a spare one (they are hard to find). Be specific when you present your problem to them and ask them for a repair price evaluation before they change anything in you laptop. You may also want to check the prices at other service centers. Hope it's not a damaged connector. Good luck.
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