Pipelining and Dec Jupiter thoughts....

[Al Kossow]

On 5/7/21 5:10 AM, Paul Koning wrote:

> Speaking of ECL:  DEC did some amazing work with ECL VLSI in the early 1990s.  There was an R&D project called "BIPS" (for "billion instructions per second") -- which aimed to build a single-chip processor that would run at a gigahertz.  That was way faster than the clock speeds of the time, and the notion was that to do this you needed to use ECL logic.

IBM ran into the same problem in the 60's. The technology they developed with Moto was used by Amdahl in his clones.

"biCMOS" was tried in the 90's. I worked with Exponential Technology on their 500MHz PowerPC. The problem with it was
the on-chip caches were too small so the CPU spent most of its time stalled.