power-on password
A password required when a computer or device is powered on, typically set in BIOS/UEFI or firmware settings.
This laptop has a power-on password set, so you need to enter a password when it starts up.
A general password; 電源投入時パスワード specifically refers to the one required at power-on.
Often synonymous, but 電源投入時パスワード is a more descriptive Japanese term.
Compound of 電源投入時 (power-on time) and パスワード (password).