The '32X' is an add-on module for the Sega Mega Drive / Genesis, developed by Sega in 1994 (under the code name 'Project Mars' - a planetary project title that for once isn't apocryphal) as a stop-gap to allow the substantial user base of 16-bit Sega Mega Drive to play cartridge-based 32-bit games (without having to shell out the $299 estimated cost of an all-new 32-bit, CD-based system) in the interim period before the Sega Saturn was brought to market. The machine was released in November 1994 in the United States (as the Genesis 32X), reaching Europe (Mega 32X) and Japan (Super 32X) in the following year.

The 32X device is shaped rather like a wide, squat, black mushroom. It plugs into the cartridge port on top of the Mega Drive model 1 or 2. Setting up the device is surprisingly not a simple case of 'plug and play'. Hooked metal brackets must first be attached to the Mega Drive's cartridge port (to shield radio interference). The Mega Drive's AV OUT must be connected via a pass-through cable to an input port on the back of the 32X so that standard Mega Drive games can be played through the 32X. (The Mega Drive models 1 and 2 have different-shaped AV OUTs, so the passthrough cable comes in two parts.) The 32X also requires its own mains adaptor. (It should also be mentioned that you can't plug a Power Base Converter into a 32X. Well, you can plug it in but it won't work. It says so in the manual.) The 32X can also interoperate with the Sega CD / Mega CD add-on if it is present, allowing for games to be released on CD-ROM with enhancements such as higher quality FMV. (Very few CD-ROM 32X games were released.)

The 32X radically enhances the graphic and sonic capabilities of the Sega Mega Drive. The palette is expanded to 32,768 simultaneous colours (no increase is made to the display resolution), and two additional PCM channels are mixed with the Mega Drive's existing sound channels. The machine also provided an additional 512kb of RAM. The 32X's twin 23Mhz Hitachi SH-2 processors (capable of 40 MIPS) puts these expanded resources to good use. The 32X is capable of drawing 50,000 textured polygons per second (don't laugh...) as well as hardware scaling and rotation.

By way of comparison, the 32X is significantly more powerful, by any measure, than the Super Nintendo (Super FX chip or otherwise- compare Virtua Racing Deluxe to Stunt Race FX, or the system's respective versions of DooM), but rather less powerful than the Sega Saturn or the Sony PlayStation. Most of the games supported the six-button joypad.

The 32X software library is rather small (fewer than 30 titles made it to market in any territory), but still manages to boast a handful of high quality games. Virtua Racing Deluxe and Virtua Fighter (reputedly developed by AM2 themselves) were very enjoyable adaptations of the hit Model 1 arcade games from a couple of years before. Star Wars Arcade was a 3D arcade port in a similar vein, and was intended as the machine's flagship launch title, although it has dated very badly. Inexplicably, arcade-perfect versions of the ancient After Burner and Space Harrier were also released, at a lower price point. (These would really only be of interest to completists, their simple gameplay and dated graphics being shallow fare without the hydraulic cabinets of the arcade originals.) As a technical showcase, Sega also commissioned a port of Id Software's DooM, which, although it shows signs of having been rushed, is surprisingly enjoyable.

Sega's original titles on the machine were of variable quality, with most being partially disguised rehashes of existing Mega Drive titles. Kolibri was a hummingbird-based shooter modelled after Ecco the Dolphin. Knuckles Chaotix was the system's Sonic game (without Sonic as a playable character). Cosmic Carnage was a clunky 2D fighting game of the kind that continues to clutter the second hand bins of game stores. Metal Head (much lauded at the time) is a first person mech game, rather like an early forerunner to Phantom Crash. Stellar Assault and Zaxxon Motherbase provided the machine with two different (and graphically impressive) takes on polygonal space shooting.

Electronic Arts (FIFA 96), Acclaim (NBA JAM TE, Mortal Kombat 2), and Core Design (B.C. Racers, Soul Star X) put out respectable third party offerings for the 32X. (All the games mentioned are reworkings of 16-bit originals, and are the best home versions of those titles.) Digital Pictures put out retooled versions of some of their FMV-based Sega CD games (Fahrenheit, Corpse Killer, Night Trap) for the 32X/CD gaming jackalope. Two rare and notable titles for the machine are Darxide (Frontier Developments) and Blackthorne (Blizzard). A great many titles were canned before they could be brought to market, mainly enhanced Mega Drive titles. The list of 32X games that the public never got to play includes Virtua Hamster, Alien Trilogy, a new Castlevania game, and an X-Men game that was reportedly received very favourably at trade shows.

The 32X unfortunately turned out to be an expensive flop. It came out too late (its lifespan sharply curtailed by the unforeseen rush to bring the Sega Saturn to market to compete with the Sony PlayStation), at too high a price point and with very limited software support (Sega's internal software divisions were understandably more concerned with Sega Saturn projects, and third party publishers, although initially enthusiastic, cancelled most of their 32X projects by late 1995 due to poor hardware sales). In the United States, the 32X suffered an early blow in the vital Christmas retail period, in the shape of Nintendo's Donkey Kong Country, a dazzling platform game that suggested to consumers that there was still life left in plain old 16-bit systems, which were comparitively cheaply priced.

The 32X can now be emulated highly accurately with the versatile Gens emulator. (The assorted processors involved result in this emulation needing a considerably faster PC than emulation of a plain old Mega Drive or SNES.)