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.
[1] Namco System 256 is an upgraded version of System 246, but the upgrades are unknown (more VRAM and faster CPU speeds likely).
[2] 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.