[MAME 2003 Reference Set (Update 2)]

• Complete MAME 0.78 ROM set with CHDs
• Complete MAME 0.78 audio samples set
• MAME 0.78 DAT file and ClrMamePro software for validation
• Original MAME 0.78 source and executable packages (mame078b and mame078s)

This is a complete set of ROMs, CHDs, and audio samples for MAME 0.78. This version of MAME, originally released in 2003, became the basis of standardized MAME emulator profiles including MAME 2003 for libretro/Retroarch/Lakka/EmulationStation/RetroPie/etc.

This reference set includes the Progetto-SNAPS datfile and the version of ClrMamePro which was used to verify the ROMs, CHDs, and samples. The TorrentZip executable included with the set was used to process each ROM and sample zip prior to distribution.

[ROM Set Format: Non-Merged] Using a Non-Merged set means that every .zip in this collection is a complete ROM that can be used stand-alone.

The question of merged, split, and non-merged ROM sets has to do with "parent" and "clone" games. The parent is the primary or original version of a game. Clones are a variant of the Parent. Here is where the differences between set types comes into play.

Clones often feature a different language or updates to the game software. Some clones are "bootleg" versions of a ROM -- for example bootlegs that remove encryption that which makes the "parent" ROM unplayable. For these and other reasons, clone ROMs are sometimes the preferred version of a game.

"Merged" and "Split" sets save drive space by consolidating the parts of the clone ROM that are identical to its parent into the parent's zip file. The only benefit to this approach is saved space. On the other hand, not all emulators support Merged and Split sets. Those set formats are also make it more challenging to manually copy individual ROMs for use with an emulator rather than using the whole set.

Non-Merged -- such as this set -- arranges all games, parents and clones, in their own stand-alone .zip files with all of the files needed to run the game. This takes somewhat more storage space but removes clone dependencies on parents, meaning you can take any of these .zip files (including clones), put them in the appropriate emulator ROM directory on their own, and they should work