Hello holly75,
Thank you for posting on the HP Forums!
I understand your computer's display will go black when an upgrade occurs. I will do my best to assist you with this issue!
This is usually caused by a software conflict or hardware failure. To determine which one, some troubleshooting will have to be done. I will start by providing this HP document: Computer Does not Start (Windows 8)
You may have already been through this document in the past. It will contain separate troubleshooting for seperate issue. Please try all of the suggested troubleshooting steps.
If that doesn't work, you should reinstall the operating system. A recovery would clean it up and allow you to restart everything fresh. Before you reinstall the operating system, you should back up everything first. This document will provide suggestions on how to do this: Backing Up Your Files
Once this is done, you could perform the recovery. Information on how to do this is provided here: Performing an HP System Recovery
If the issue is software related, you will be able to resolve it by this point. If not, I would contact HP phone support. They will either replace it or service it, or provide a solid fix. Unfortunately, there is probably some sort of hardware fault if the issue cannot be resolved. You can utilize this website to learn how to contact HP appropriately, based on your region: Contact HP Worldwide
I believe this troubleshooting will assist you. Either way, please provide your results. Thanks again for posting on the HP Forums. Have a great day!
Mario