¶ Technical data
- Manufacturer: Sega
- Year of release: 2000
- Type: arcade system
- CPU: Hitachi SH-4 128-bit @ 200 MHz
- Video: NEC/VideoLogic PowerVR2 (CLX2)
- RAM: 32 MB main memory, 16 MB video memory, 8 MB sound memory
- Sound chip: Yamaha AICA (ARM7 core), 64 channels
- Resolution: 640x480
- Media: GD-ROM, loaded into memory through a DIMM board
- Controller: mandatory
¶ Presentation
The NAOMI GD-ROM System is not a new machine but an evolution in how games were distributed on the NAOMI platform. From 2000 onwards, Sega replaced the expensive ROM cartridge with a GD-ROM drive — the high-density disc already used on the Dreamcast — paired with a DIMM board acting as a buffer.
The principle is simple: when the cabinet boots, the contents of the GD-ROM are copied into the DIMM board memory, then the game runs from that memory, with no disc access during play. Operators paid far less for their games, and Sega could publish updates without manufacturing new boards.
The GD-ROM catalogue is that of the NAOMI's late commercial life, with many Sega titles and a strong third-party presence: the Virtua Tennis games, Guilty Gear XX, Capcom vs. SNK 2, Ikaruga, Border Down and the Melty Blood series. It is also the medium on which NAOMI 2 games were distributed.
¶ Emulators
New in Recalbox 10.1: Flycast moves to flycast-next, which becomes the default emulator on RPi5.
Emulator availability per board:
| Emulator | RPI3/RPI02W | RPI4/400 | RPI5/500 | OGA/OGS/RG351 | PC | RG353 |
|---|---|---|---|---|---|---|
| Libretro Flycast | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ |
| Libretro Flycast-Next | ✅ | ✅ | ✅ | ❌ | ✅ | ❌ |
Flycast-next is not available on OGA/OGS/RG351 nor on RG353: those boards use Flycast.
Flycast is the default emulator on every board, except on RPi5/500 where flycast-next takes priority. Both cores offer high compatibility and speed and work on a CRT display. Netplay and softpatching are not available on this system; RetroAchievements are supported, as are light guns (recommended).
To play on a real cabinet, Recalbox 10.1 brings Recalbox JVS support (firmware 2.9) — the interface for recent JVS-standard cabinets, presented on its Kickstarter — and automatic arcade stick configuration on every system. For a cabinet with a JAMMA harness, the Recalbox RGB JAMMA 2 kit is what you need.
¶ BIOS
| File name | Description | MD5 | Emulators |
|---|---|---|---|
naomigd.zip |
NAOMI GD-ROM BIOS (mandatory) — several revisions accepted | 288cde03a112e7726fa8093e05d46853 416b5914acb3d0b4a190a1d358c8710d bd9f19b4be0692e92e272d0eb82402f7 be57d3744e71a3396fb8dc59830e880a |
Flycast, Flycast-Next |
Place your BIOS file like this:
/recalbox/share/bios/dc/
└── naomigd.zip
The GD-ROM BIOS does belong in the
dc/folder, shared with the Dreamcast and the other systems emulated by Flycast. Keep the file zipped, and do not rename it.
¶ Roms
Put your games in:
/recalbox/share/roms/naomigd/
Supported extensions: .zip .7z
Games are MAME-style romsets: leave them zipped, do not rename or extract them. Raw GD-ROM images (.gdi, .chd) are not accepted as-is in this folder. The romset must match the version of Flycast shipped with Recalbox — a romset that is too old or too recent is the most common cause of a game refusing to start.