> From: Mattis Lind > I cannot figure out which early machine it comes from.
They're called 'System Modules': http://gunkies.org/wiki/System_Module and they were used from the PDP-1 through (I think) the PDP-7; at least, this PDP-7 internals image: https://www.soemtron.org/images/jpgs/decimages/sn113robertjohnson85680004.jpg seems to show System Modules at the top, and FLIP CHIPs at the bottom. (I'm pretty sure even the first PDP-8 - the 'straight 8' - uses only early FLIP CHIPs - transistorized ones.) The DEC brochure for it (P5141) is a little puzzling; it says (p. 2) that "INTEGRATED CIRCUITS are basic elements of the low cost, newly designed silicon FLIP CHIP modules used throughout PDP-7", but AFAIK, the first FLIP CHIPs (R-series, B-series, etc) were all transistors; the later M-series were the first ones to have ICs. Maybe this is some old meaning of "integrated circuits"? Noel