[daneel_w]

The Acorn Archimedes came with Acorn branded CPUs (the "ARM250" IIRC) already in the late 80s. I can't recall what company made the chips for ARM at that time, but in the later Archimedes models it was VLSI.

[rwmj]

VLSI from the very start according to https://en.wikipedia.org/wiki/ARM_architecture_family#ARM1

[daneel_w]

A quick Google image search shows me ARM250TG chips, Acorn-ARM branded, from "MITEL" and "GPS".