Mac CPU upgrades were a big market, though. In the 68K era you had things like Daystar cards and the Radius Rocket, and Apple themselves made a PPC 601 card. So

Mac CPU upgrades were a big market, though. In the 68K era you had things like Daystar cards and the Radius Rocket, and Apple themselves made a PPC 601 card. Sonnet even made them for allegedly unupgradeable machines, like the 7200 G3 upgrade that took over a PCI slot. The extension shunted everything to the CPU on the card and disabled the 601 soldered to the board.