Thank you for visiting the HP Support Forums and Welcome. I have read your thread on your Compaq Presario CQ61 Notebook and getting a blank or black screen on startup. Try performing a hard reset. When performing a hard reset please note remove any and all USB devices, and remove memory cards from the card reader slot. Disconnect all non-essential devices. If that does not help try to turn on the computer you start to press F11 repeatedly till the menu opens. You can do a system restore.
Hope this is helpful.
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