How to Update
PS2 BIOS for PCSX2

The PS2 BIOS Does Not "Update"

Unlike PC firmware or an operating system, the PS2 BIOS was permanently written to a chip inside each hardware unit at the factory. Sony did not release patches or downloads for it. The BIOS version is fixed to the console's hardware revision.

When people search for "how to update PS2 BIOS", they typically mean one of three things:

• Switching from an older BIOS version (e.g. v1.00) to a newer one (e.g. v2.00) for better game compatibility
• Replacing a corrupted BIOS file with a fresh download
• Updating the PCSX2 emulator itself — which is the one that does receive updates

Switching to a Different BIOS Version

If a specific game is not working with your current BIOS, try a different version. You can have multiple BIOS files in your BIOS folder simultaneously and switch between them in PCSX2 settings before loading a game.

1. Download the target BIOS version from the download page (e.g. SCPH-70012 if you currently have SCPH-39001).
2. Extract and place the .bin file into your BIOS folder alongside your existing files.
3. In PCSX2, go to Settings → BIOS. Both versions will appear. Select the new one.
4. Load your game and test. If it works, leave it on the new version. If not, switch back.

Replacing a Corrupted BIOS File

If PCSX2 flags your BIOS as invalid or the file size is not exactly 4 MB, the file is corrupted. Delete it, re-download, extract, and copy fresh. See Corrupted BIOS Symptoms for full details.

Updating PCSX2 Itself

This is what matters most for compatibility improvements. PCSX2 releases regular updates that improve how games run, add cycle-accurate CPU timing, fix graphical glitches, and improve compatibility with problem titles — all without changing the BIOS file.

1. Visit the official PCSX2 website at pcsx2.net.
2. Download the latest nightly or stable build for your operating system.
3. Install it over your existing installation. Your BIOS files, settings, and save states are preserved.