Path: utzoo!attcan!uunet!husc6!ukma!cwjcc!tut.cis.ohio-state.edu!accelerator!icarus.eng.ohio-state.edu!kaul
From: kaul@icarus.eng.ohio-state.edu (Rich Kaul)
Newsgroups: comp.arch
Subject: Re: ETA-10: CMOS or ECL?
Summary: CMOS
Message-ID: <805@accelerator>
Date: 14 Oct 88 17:33:55 GMT
References: <3539@phri.UUCP>
Sender: news@accelerator
Organization: The Ohio State University Dept of Electrical Engineering
Lines: 17

In article <3539@phri.UUCP> roy@phri.UUCP (Roy Smith) writes:
>	At one point I said something like "The CPU is all ECL, right?",
>and he said, "No, it's CMOS".  This really surprised me.  Is it really
>CMOS?  I always thought of CMOS as pretty slow stuff, just pushing the
>speed of normal TTL, and certainly not supercomputer stuff.

It's CMOS.  CMOS can be pretty fast when you get the integration level up
and pay some attention to speed in the design.  From what I've seen, ETA
did a pretty good job on that machine. 

The really sexy version of the ETA is CMOS cooled in liquid nitrogen.  This
baby really cooks (or is that freezes? :-)  The cooling in nitrogen gets
you a factor of 2 in speed when you use CMOS devices.  Of course, your
mileage will vary with your process, supply voltages, etc., but a factor of
2 is pretty common at nitrogen temperatures.
-=-
Rich Kaul				kaul@icarus.eng.ohio-state.edu