Here’s a promo video, with a glossy start and then a short bit from each of several engineers describing the technology needed and invented for the C90.
To bring this system to you the people of Cray Research have pushed the limits of technology in every phase of development and manufacture
… to sustain that bandwidth the new architecture was first verified on a Cray YMP using simulation software in fact the YMP was used extensively during development to shorten development time and test literally millions of options long before the first hardware was assembled
Uploaded by Derek Foulk, who is also uploading some Cray 1 in-house training videos…
Cray-1 internals - technology briefs from 1984