Under Defeat ROM Download (NAOMI)

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The Sega NAOMI (New Arcade Operation Machine Idea) is an arcade system board released in 1998 as a successor to Sega Model 3 hardware. It uses the same architecture as the Sega Dreamcast, and stands as one of Sega’s most successful arcade systems of all time, along with the Sega Model 2.

The NAOMI debuted at a time when traditional arcades were on a decline, and so was engineered to be a mass-produced, cost-effective machine reliant on large game ROM “cartridges” which could be interchanged by the arcade operator. This is contrary to systems such as the Model 3, in which each board, despite sharing largely the same specifications, would be bespoke, with the built-in ROMs being flashed with games during the manufacturing process. This is not the first time such an idea was utilised by Sega, but never before had technology been used for a cutting-edge Sega arcade specification.

Unlike most hardware platforms in the arcade industry, NAOMI was widely licensed for use by other manufacturers, many of which were former rivals to Sega such as Taito, Capcom and Namco. It is also one of the longest-serving arcade boards, being supported from 1998 to 2009. It is a platform where many top-rated Sega franchises were born, including Virtua Tennis, Samba de Amigo, Crazy Taxi and Monkey Ball.

The NAOMI was succeeded by the Sega Hikaru and Sega NAOMI 2 boards, though having out-lasted the NAOMI 2, Hikaru and Sega Aurora. The Sega Chihiro, or possibly even the Sega Lindbergh, could also be seen as successors.

May 25, 2025