Re: The Seymour Cray Era of Supercomputers

On Sun, 18 May 2025 15:23:03 +0000, Michael S wrote:

On Sun, 18 May 2025 05:46:37 -0000 (UTC)
Thomas Koenig <tkoenig@netcologne.de> wrote:
>

MitchAlsup1 <mitchalsup@aol.com> schrieb:

Did the book relate the story of why CRAY-1 presented a DC-load to
the power supply:: that is, the ECL gates were all of the form where
they would switch 20 ma into either the true or the complement out-
put and thus have no AC energy at the power supply level ??

>
That they didn't mention.  They stressed his decision to build
a machine which had good all-round performance, unlike the
predecessors like the STAR or the Texas Instruments ASC (which I
had never heard or read of).
>

>
May be, that aspect of CRAY-1 was different from STAR and ASC, but not
different from CDC 6600 or 7600 or from top models of Cyber-170 series.

Yes, but the CDC 6600 and 7600, while powerful computers, were ordinary
computers. They were not vector machines. The STAR and the ASC were
vector machines - and because, unlike the Cray-I, vectors was the only
thing they were good at, Amdahl's Law killed them.
John Savard