FinalBurn Neo (FBNeo) – a MAME derivative – uses a different, newer container: .neo files. FBNeo still needs a neogeo.zip BIOS, but the requirements are looser. If you use RetroArch with the "FinalBurn Neo" core, place neogeo.zip in the system/fbneo/ folder.
This is the uncomfortable truth. Distributing copyrighted BIOS ROMs is in most jurisdictions. mame neogeo bios
To understand why you need a neogeo.zip file for MAME, you must first understand what a BIOS actually is. FinalBurn Neo (FBNeo) – a MAME derivative –
Older MAME versions (pre-0.162) used a different file set. If you are using an old BIOS file with a new MAME, you will get "ROM CHECKSUM ERROR." mame neogeo bios
If you want, I can: