Launch a game that heavily relies on a BIOS. For example, try Metal Slug 5 (mslug5.zip). If the Neo Geo splash screen appears (the green screen with the SNK logo), your BIOS is working. If you get a blue screen with text like "NO ROM" or "SYSTEM ERROR," your BIOS file is incorrect or corrupt.
Cause: Missing BIOS ZIP, or the ZIP has the wrong internal contents.
Solution: Ensure you have, for example, neogeo.zip in your roms folder. Open that ZIP and verify it contains files like sp-s2.sp1, usa_2slt.bin, and vs-bios.rom (names will vary by version). For 0.147, a valid neogeo.zip should be around 1.8 MB. mame bios roms 0 147
Believe it or not, the “obsolete” 0.147 BIOS set is perfect for: Launch a game that heavily relies on a BIOS