The story of this specific BIOS (the v2.20 or similar slim variants) is one of . The code inside the SCPH-70004 was stripped of the bloat. It was designed to boot faster, recognize DVD-RWs, and crucially, it introduced the Internal Power Supply.
For users of PCSX2 or RetroArch, the SCPH-70004_BIOS_V12_EUR_200.BIN is a "gold standard" for PAL region games. It provides excellent timing accuracy and minimal glitching compared to later Slim BIOS versions (v2.20+). scph 70004 bios
Probably a bad dump or using the BIOS on the wrong PCSX2 build. Fix: Re-dump and verify CRC with known good hash from PS2 BIOS database (for identification, not piracy). The story of this specific BIOS (the v2
Filenames are often case-sensitive depending on the emulator front-end you use. Verification: You can use tools like the BIOS Checker Fix: Re-dump and verify CRC with known good