NeoBox vs NeoCD/PS2

NeoBox is a native macOS app with a built-in Geolith Neo Geo emulator; users provide their own ROMs and BIOS files. It accepts MAME-format ZIPs, scans ROM folders, organizes recognized games with bundled metadata, and watches folders for additions. The maker says metadata covers 158 games, including MVS and AES titles through KOF 2003. NeoBox provides timestamped save states, numbered slots, per-game memory cards, and F12 screenshots. Display options include an optional Metal-rendered CRT shader, Auto 4:3, and pixel-perfect integer scaling. Xbox, PlayStation, Switch Pro, and MFi controllers work over USB or Bluetooth, with keyboard input also available. Users can select external MAME instead of Geolith; the maker says the library, save states, and bindings carry over. NeoBox requires macOS 14 or later and is native for Apple Silicon. The Mac App Store listing describes it as signed and notarized. The NeoBox: Neo Geo Player plan costs $14.99 as a one-time purchase.

NeoCD/PS2 is a free, open-source NeoGeo CD emulator for the Sony PlayStation 2. It is a port of NeoCD/SDL, adapted to replace SDL components with PS2-native libraries using PS2SDK. Games load directly from the CD-ROM. Video offers PAL/NTSC auto-detection and selection, while the in-game menu includes filtering, fullscreen video, and frameskip controls. The emulator supports two controllers, stereo sound emulation, and CDDA playback. NeoGeo CD memory card support uses 45 KB on a PS2 memory card. ZIP support is limited to the BIOS, and the NeoGeo CD BIOS is not included; users must find it or dump it from their own system. The releases page lists version 0.6c with CDDA fixes, including an auto-loop feature. Listed issues include sound problems when the frame rate is below full speed, timing issues, graphics glitches in some games, and needing to reset the PS2 to exit the BIOS. The project is distributed under GNU General Public License version 2 and says use is at the user's own risk; the README says it should only be used with games the user legally owns.