If that don't Work Try F1 or F2 or F8 or F11 thru F12 Depending on your Model for the Computer Setup, This system is not Related to the Windows, If this does not Show any thing On Boot up when you press those Keys for the Setup. and there still a black screen then there may be a problem with the your Circuitry,Take a Look here:
HP Notebook PCs - Troubleshooting Black Screen Displays with No Error Messages During Startup or Boot
http://tinyurl.com/ps65u24
The link to HP there was way to long to even paste in.