these RTL or what?

Tore Sinding Bekkedal toresbe at
Tue Dec 4 18:19:44 CST 2007

On Fri, 2007-10-05 at 12:42 -0400, William Donzelli wrote:
> > VAX9000 built of ECL100K, fastest of the fast.  The second most common
> > use of TTL was in very high speed instrumentation and specifically frequency
> > counters and UHF PLLs.
> If the 9000 series was till using 100K, DEC must have been sleeping.
> By the 9000s development period, ECL was beyond 100K. I am not sure,
> but 10E may have been out by then. 10G maybe as well, but using that
> leads to insanity.
> But one thing I notice about DEC's ECL machines (9000, KL10) - for
> being ECL, there sure were ssssllloooowwwww.

Recently, I actually had a chance to speak with one of the original
engineers behind the VAX 9000. He said that they had the Aquarius
running very stably (and completely quietly) when they were told that
they had to switch the machine to air-cooled. 

The reason was that a business analyst had decided that supercomputers
were no longer selling, and the main indicator of a supercomputer was
liquid cooling. They had to cut the cycle speed down quite

-Tore :)

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