The top side of the main board of a Brainstorm accelerator for a Mac Plus, featuring a Toshiba TMP68HC000P16 CPU and a custom "ASX-6" IC, copyright 1991 Brainstorm.

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1. Keith Kaisershot (blitter@mastodon.social)'s status on Wednesday, 31-Jan-2024 04:26:32 JST Keith Kaisershot

   This is the Brainstorm accelerator for the Mac Plus. It plugs into a socket clipped to the top of the Plus's standard 68000 CPU. Providing its own replacement 68HC000P16 and combined with a couple of helper chips, the Brainstorm gives the Mac Plus a significant speed boost, jumping from ~8MHz to ~16Mhz. Benchmarks on LEM as proof: https://lowendmac.com/2000/mac-plus-with-16-mhz-brainstorm-upgrade-benchmarked/