Super FX

Lore & Background

The Super FX chip design team included engineers Ben Cheese, Rob Macaulay, and James Hakewill. While in development, the chip was codenamed 'Super Mario FX' and 'MARIO'. 'MARIO', a backronym for 'Mathematical, Argonaut, Rotation, & Input/Output', is printed on the face of the final production chip. The chip's name would lead to an urban legend that 'Super Mario FX' was a video game in development for the SNES.

According to Argonaut Games founder Jez San, Argonaut had initially intended to develop the Super FX chip for the Nintendo Entertainment System. The team programmed an NES version of the first-person combat flight simulator Starglider and showed it to Nintendo in 1990. The prototype impressed the company, but they suggested developing games for the then-unreleased Super Famicom due to the NES's hardware becoming outdated. Shortly after the 1990 Consumer Electronics Show held in Chicago, Illinois, Argonaut ported the NES version of Starglider to the Super Famicom, a process which took roughly one week according to San.

Nintendo later considered integrating the Super FX chip into certain Super Famicom and SNES hardware revisions and add-on plans. Jez San said the chip was completed too late for the Japanese Super Famicom launch but was discussed for inclusion in a subsequent SNES hardware revision for the North American market. He also recalled that during early talks between Nintendo and Sony about a planned SNES CD-ROM peripheral, the companies initially intended for the CD add-on to incorporate the Super FX chip to provide 3D acceleration.

Reader's Guide

The Super FX chip is used to render 3D polygons and to assist the SNES in rendering advanced 2D effects. This custom-made RISC processor is typically programmed to act like a graphics accelerator chip that draws polygons to a frame buffer in the RAM that sits adjacent to it. The data in this frame buffer is periodically transferred to the main video memory inside of the console using DMA in order to show up on the television display. Because of high manufacturing costs and increased development time, few Super FX based games were made compared to the rest of the SNES library. Due to these increased costs, Super FX games often retailed at a higher MSRP compared to other SNES games. Game cartridges that contain a Super FX chip have additional contacts at the bottom of the cartridge that connect to the extra slots in the cartridge port that are not otherwise typically used. Therefore, Super FX games cannot be plugged into cartridge adapters which predate the release of Super FX games, including cheat devices such as the Game Genie. An emulated implementation of the Super FX written by Randy Linden—dubbed as the 'Super FX 3'—was used in Limited Run Games' 2025 physical re-release of Doom for the Super NES. The Super FX 3 runs on a Raspberry Pi RP2350 built into the Doom cartridge, running at 150Mhz and replicating the functionality of the Super FX chip while offering improvements such as a higher frame rate. A year later, a ROM hack of Star Fox was released which takes advantage of the Super FX 3 implementation.

Did You Know?

• Argonaut initially intended to develop the Super FX chip for the NES, and showed Nintendo a prototype of Starglider in 1990.
• The first version of the Super FX chip is clocked with a 21.4 MHz signal, but an internal divider halves it to 10.7 MHz.
• An emulated implementation called 'Super FX 3' was used in a 2025 physical re-release of Doom for the Super NES, running on a Raspberry Pi RP2350 at 150 MHz.