Essential if you want to play games at 50Hz or regional European releases.

AetherSX2 requires a file usually named SCPH-77001.bin (or similar numbers). Because this is copyrighted Sony software:

This guide covers everything you need to know about the 4MB BIOS files, where they come from, and how to install them safely. What is the AetherSX2 BIOS?

Select the imported BIOS as your default system and proceed to the game directory selection. Troubleshooting Common Issues