Need Info on DEC 11/84 Board, M8190/thread drift

From: Allison J Parent <allisonp_at_world.std.com>
Date: Sun Oct 18 22:12:21 1998

< bit small! Nothing on the scale of the Pentium II has ever been
< achieved with transistors, never mind relays, and I'm sure they
< tried. For example, it would be possible to place transistors at
< 1 per cubic inch, and have the cool adequately, but it's clearly

Your unaware of many systems of the 60s that were large on performance
and transistors. Your one transistor per cubic inch is far to low.
I've worked with cordwood modules that were more in the 6 per cubic
inch. Even flat boards were fairly dense.

What is missed if the PII uses transistors where other logic systems
would employ resistors, capacitors and pulse transformers. Also CMOS
requires two transistors to do what can often be done with one using
alternate forms of logic.

What would be hard to attain is the extreme speeds and that is limited
by incterconnections. Putting a few or alot of transistors on one die
is not a speed matter in itself. The shrinking of the interconnectivity
IE: shorter wires is! When machines got to the Cray speeds the length of
wires was an issue as electrons propagate at 1ns a foot. To put that in
perspective a PII running at 333mhz is clocking at 3ns! Distributing
high speed signals around computers is an art, still.

< never been attempted, because if it were, there would be boxes
< to plug into a PC XT to get Pentium II speeds.

The XT bus and IO are slow, even using a PII would be slowed. BEsides it
was done using 386s...

Allison
Received on Sun Oct 18 1998 - 22:12:21 BST