discrete transistors

From: Allison J Parent <allisonp_at_world.std.com>
Date: Mon Oct 19 17:55:38 1998

< A 486 is certainly faster in terms of CPU horsepower. But a 486
< has no I/O horsepower whatsoever. Nor does any sort of Pentium.

Problem with most all of the high power processors. The VAX series were
only ok in that respect and were better if there were external IOPs.

< It's certainly *possible* to add intelligent I/O channels to an x86 mach

The hottest machine I've played with was a hacked xerox XP12 laser printer
controller. It was a 8mhz 8086 and a 8089(IOP). It could beat any 8086
system cold (using s100 and multibus systems as standard). Later I would
see a 8086 multibus system with two 8089s running CPM-86 and it was far
faster than the then new AT.

The speed of the IO systems and it's peripherals is everything. I know
this from building a multiprocessing/multitasking system in the early
1980s using four z80s in a loosely coupled SMP. The array of z80s, 8085s
and 8749s around them to do IO was where the real performance could be
found.

Allison
Received on Mon Oct 19 1998 - 17:55:38 BST