In MAME, the setup for BIOS files is different than in some other emulators:

To play Neo Geo games in MAME, you need a specific set of system files known as the , usually packaged as a file named neogeo.zip . This file contains the essential instructions the emulator uses to mimic the original hardware, including both the MVS (Arcade) and AES (Home Console) systems. Why the BIOS is Necessary

Many users choose to include the (UniBIOS) within their neogeo.zip . Developed by Razoola, this custom BIOS adds several modern features to the emulation experience: neogeo.zip in mame4all - what and where to put exactly?

: Ensure your neogeo.zip matches the version of MAME you are using. For example, newer builds of MAME (like 0.202 and later) require updated BIOS files such as sp1-u4.bin that older sets might lack. The Universe BIOS (UniBIOS)

: Do not unzip the neogeo.zip file; MAME is designed to read the necessary files directly from the archive.