Thank you for choosing Windows 8 and posting your query on Microsoft community.
From your issue description I understand that after installing Windows 8 its showing black screen.
To help you further with this issue I need more information, so please answer the following questions.
1. Where exactly are you getting the black screen?
2. Do you get any error message or error code?
3. What is the make and model of the computer?
4. How did you install Windows 8?
5. Did you use upgrade assistant before installing Windows 8 on the computer?
Please answer these questions so that I can rectify your issue as soon as possible.
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