Most emulators expect specific names. You may need to rename psxonpsp660.bin to scph5501.bin or whatever your specific core requires. Placement: Place it in the system folder of your emulator.
In the world of video game emulation, the BIOS (Basic Input/Output System) is a critical software layer. It's the first code a console runs when powered on, handling basic hardware functions like managing the memory card, loading the CD player, and initializing the system. An emulator without the correct BIOS is like a car without an engine—it might look the part, but it won't get you where you want to go.