< So don't underestimate the power of a micoprocessor. We < just bring them unde a yoke, no 'real' processor ever < har to carry. Oh, I don't. I've said Z80s are not as shabby as some of the latterday retrorevisionists would think. I've never seen a i286 running anything (OS) that really used all the raw power in any useful way other than in embedded tasks. That view come from mostly ISA bus PC implementations while interesting are really not best possible performance. At the other end of the line there were some monster transistor based systems that offered stellar performance at a price. Some of the SSI (small scale integration) IC machines of the late 60s bumped up those numbers or shrank/lowered their cost. Allison