While PSXonPSP660.bin boasts roughly 99% compatibility with the PS1 library, a handful of obscure games that relied on specific, undocumented original hardware quirks may fail to boot. If you encounter a rare game that freezes, temporarily switch your emulator settings back to a region-specific original hardware BIOS like SCPH1001 .
If you cannot locate this specific file, or if it does not work for your setup, consider these alternatives: psxonpsp660bin bios file