Having owned one of these great machines, I can testify to the hinge problems I had towards the end of its life. As the hinge starts to break, the display cables within the hinge can start to fray and break. You've got a few options:
* Continue to use the laptop until the screen is unusable. At that point, you can connect a display, keyboard, and mouse and close the lid. You have to watch out for heat with the lid closed, but your computer will live on. Alternatively, you could make it run [http://www.ifixit.com/Answers/View/6414/Battery+and+LCD+panel+are+failing%2C+can+I+operate+it+%22headless%22+safely|headless].
* If you want to fix the problem, you'll have to replace the [guide|99|display]. Unfortunately, you could probably buy an Intel MacBook for the price of the display, so this isn't really price-effective.
Hope this helps!
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