Because no manual I can't be exact but many old PCs had a power up setting in the BIOS. Again, I can't be specific. If you find a manual, please supply a link.
Bob
HP Pavilion Xl 1953
Win XP Home
I was given this older computer. It is plugged into a power strip. After I do a proper shutdown. I turn the master switch off at the power strip. When I turn the power strip back on the computer lights up and automatically starts to boot up.
I am sure I am missing something in the power mgmt section but not been able to stop this issue. Your instruction will be appreciated.

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