Don't worry as I'll be glad to help, To get the answer to this question, you can stop the hard drive test now and restart your computer if you're still experiencing same black screen issue then I would suggest performing system factory reset will put the computer back to the original factory settings in this way all corrupted and outdated software will be removed.
The HP Cloud Recovery Tool allows you to download recovery software to a USB drive. You can use the downloaded recovery image file in order to install the Windows operating system.
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