There are a number of possible reasons after checking what you have so far. Have you checked that the video card has not been disturbed inside the computer?. Try starting your computer in safe mode, see link below. Just in case you have a driver problem.
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There are a number of possible reasons after checking what you have so far. Have you checked that the video card has not been disturbed inside the computer?.
Try starting your computer in safe mode, see link below. Just in case you have a driver problem.
http://windows.microsoft.com/en-gb/windows/start-computer-safe-mode#start-computer-safe-mode=windows-7