Namco System 246

The Namco System 246 is a development of the Sony PlayStation 2 technology as a basis for an arcade system board. It was released in December 2000 on its first game "Bloody Roar 3". Like the Sega NAOMI, it is widely licensed for use by other manufacturers. Games such as "Battle Gear 3" and "Capcom Fighting Evolution" are examples of System 246-based arcade games that are not Namco products.
Specifications.
Namco System 256 is an upgraded version of System 246 but the upgrades are unknown (more VRAM and faster CPU speeds likely).
Namco Super System 256 is the same as regular Namco System 256 but it has the gun board integrated, though this variant was only used in "Time Crisis 4".
Namco System 147 is similar to 246 but does not use a DVD-ROM drive, instead it has ROM chips on the system board.