NeoCD/SDLx Unleashed vs NeoCDRX

NeoCD/SDLx Unleashed is a free Neo Geo CD emulator for the original Xbox. It runs many original Neo Geo CD games and reads real discs in ISO9660 format. The emulator does not support bin/cue or iso/mp3 images and requires an uncompressed 512 KB system BIOS named neocd.bin; the download page says a BIOS copy is permitted only for owners of an original Neo Geo CD console. It supports one or two players, full CDDA audio, region selection and memory cards. Display modes include 480p and 720p, selected according to dashboard settings. Video filters are AdvanceMame2x, Simple2x, SuperSai2x, SuperEagle and Scanline. Source code is released, and the download is a 448.6 KB ZIP attachment with no Digiex registration required. The page reports miscellaneous sound and timing issues and provides the program without warranty. The listed platform is the original Xbox. AES and MVS emulation, plus other related SNK arcade systems, are not supported.

NeoCDRX is a free homebrew emulator for Neo Geo CD and CDZ games on GameCube, Wii and Wii U through Virtual Wii. It supports region settings for USA, Europe and Japan, which provide different languages and can affect some game content. The listed processor cores are Z80 3.6 and M68000 3.3, and audio controls include a three-band equalizer for music and sound effects. Supported controllers include Wii Remote, Wii Remote Plus, Wii Remote with Nunchuk and GameCube controller. Media options include SD/SDHC, USB and DVD, plus GameCube options WKF and IDE-EXI V1. Virtual memory card saves can go to SD or USB, or to a physical GameCube memory card. Setup requires a Neo Geo CD/CDZ BIOS file named NeoCD.bin in NeoCDRX/bios. Each game goes in its own folder under NeoCDRX/games, with an mp3 subfolder for music. Wii and Wii U Virtual Wii installations are packaged for Homebrew Channel; using the Wii version requires a way to run unsigned code. The README describes the project as GPL open source, while GitHub lists LGPL-2.1.