Mame 2003 Reference Romset -

The answer was to port the 2003 version of MAME to the Libretro API, creating (and later the "Plus" and " Xtreme" variants). It became the default standard for retro handhelds because it was optimized for the exact level of hardware power these small devices possessed.

Newer versions of MAME prioritize extreme accuracy, which requires significant CPU power. MAME 2003 strikes a balance, allowing it to run thousands of games at full speed on devices like the Raspberry Pi 3 or older mobile phones. mame 2003 reference romset

All versions of a game (parent and clones) are inside a single zip. Necessary Supplementary Files Some games (like Donkey Kong ) require a separate folder containing The answer was to port the 2003 version