Subject: Re: My first step towards a VAX 11/785 :-)
To: Gunther Schadow <gunther@aurora.regenstrief.org>
From: Chuck McManis <cmcmanis@mcmanis.com>
List: port-vax
Date: 07/09/2001 21:22:05
At 10:36 PM 7/9/01 -0500, Gunther Schadow wrote:
>Sunday I found five large boxes in front of my house. Got 56 cards
>ready to put into a 11/785 cabinet. What surprized me is how different
>these cards look and feel from the VAX 6400 cards. They are larger
>in size, yet thinner, and lighter in weight. Also the chips on the
>cards look much less impressive than the VAX6400 chips. Looks like
>all small 10 to 20 pin TTL DIL style ICs. Is that right? Why am I
>missing a set of larger square ICs holding CPU etc? Is this because
>the 11/780 isn't a microprocessor machine but rather several boards
>per CPU with a printed circuit for what's usually engraved in silicone?

For one it is 'silicon' the element rather than silicone the synthetic 
rubber that was a major component of artificial breasts. And yes, as you've 
surmised, the CPU consists of many generic gates wired together to form the 
CPU. No large scale integration, no custom integrated circuits. You can see 
why these machines were so slow and used so much power (lots of chips, lots 
of delays)

--Chuck