A little more digging, and the crossbar in the B 5000 series idea came from the D 825 SAGE backup system AN/GSA-51 ref. Burroughs B 5000 conference Sep 85, archived by CBI (page 18) other references can be found on line to the D 825 being the first multiprocessor, and to the memory/processor switch http://www.cs.uiowa.edu/~jones/arch/notes/35cross.html http://www.fas.org/nuke/guide/usa/airdef/buic.htm http://www.cc.gatech.edu/gvu/people/randy.carpenter/folklore/v3n1.html