Failure to boot

[MKJha]

My HP Pavillion 510-127c desktop stopped booting a couple of weeks ago. Suspecting hard drive failure, I installed a new hard drive and re-installed Windows 10 using Windows Re-installation media created from another machine. The desktop was able to boot once and everything seemed fine e.g. I can browse the internet. But if I shut it down and restart, it again fails to boot. I don't feel like buying a new machine until I have exhausted all the options. Does anyone have any suggestions for further troubleshooting?

Note: I happened to find a way to get the machine to boot by the following sequence of actions: 1) Disconnect hard drive 2) Start the machine and power it off 3) Connect the hard drive 4) Power the machine. I happened to find this hack as I was failing to access Bios settings during start up when I read that Fast startup option may prevent getting into bios settings. Of course, I can't operate the machine on daily basis using the hack I stumbled upon. Not sure if this points to any issue in BIOS settings but couldn't figure out. Please Help.

[Lil_Boy_Blue]

Hi

https://www.techwalla.com/articles/how-to-check-the-cmos-battery

is my first thought.

And then perhaps try a relatively in-expensive repair.

https://www.amazon.co.uk/dp/B003UOYB8A?tag=duckduckgo-brave-uk-21&linkCode=osi&th=1&psc=1

after that the BIOS is suspect.

If in doubt please ask.

[MKJha]

Replaced the CMOS battery with a working one. However, the problem persists.

[Lil_Boy_Blue]

Disable fast startup.

I doubt there is the equivalent for a Desktop, this is for a laptop. So may be it is a BIOS option.