The differences are in packaging, pinout, maximum supported ROM size, and internal clock speed.

All versions of the Super FX chip are functionally compatible in terms of their instruction set. The final known revision is the GSU-2-SP1. The design was revised to the GSU-2, which is still 16-bit, but this version can support a ROM size greater than 8 Mbit. Both the MARIO CHIP 1 and the GSU-1 can support a maximum ROM size of 8 Mbits. The GSU-1 however runs at the full 21.47 MHz. Both versions are clocked with a 21.47 MHz signal, but an internal clock speed divider halves it to 10.74 MHz on the MARIO CHIP 1. From 1994, some boards have an epoxy version, and later a first revision is labeled GSU-1. This chip has at least four revisions, first as a surface mounted chip labeled 'MARIO CHIP 1' (Mathematical, Argonaut, Rotation & I/O), commonly called the Super FX, in the earliest Star Fox (1993) cartridges. Super Mario World 2: Yoshi's Island uses the Super FX 2 for sprite scaling, rotation, and stretching. It is typically programmed to act as a graphics accelerator chip that draws polygons and advanced 2D effects to a frame buffer in the RAM sitting adjacent to it. The Super FX chip is a 16-bit supplemental RISC CPU developed by Argonaut Software. Super FX renders 3D polygons in Star Fox.

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