angelus9151 This is a good source to help you understand which bios and which folders. This is what I started learning to begin with hope this helps https://github.com/retropie/retropie-setup/wiki/PlayStation-1
kermitasuarus Are you putting them into folders? Or are you just throwing the files into the bios folder? Becouse for some reason it will not work if they are in another folder within the bios folder
