First demonstrated in 1998 at JAMMA, the Sega NAOMI (New Arcade Operation Machine Idea) is the successor to the Sega Model 3 hardware.
A development of the Dreamcast home game console, the NAOMI and Dreamcast share the same hardware components, but the NAOMI has twice as much system memory & video memory, and four times as much sound memory. Multiple NAOMI boards can be 'stacked' together to support multiple-monitor output.
The NAOMI arcade-board features 168 MB of solid-state ROMs or GD-ROMs using a custom DIMM board and GD-ROM drive. In operation, the Naomi GD-ROM is read only once at system powerup, downloading the disc's contents to the DIMM-Board RAM. Once the download is complete, the game executes out of RAM, thereby reducing mechanical wear on the GD-ROM drive.