The IBM Enterprise System/9000 Type 9121 air-cooled processor

The IBM Enterprise System/9000™ Type 9121 air-cooled processor achieves, with the same or reduced physical floor space and power levels, a performance level equal to or greater than those of previous IBM processors. This performance level was attained by a combination of design innovations: a new air-cooled thermal conduction module (TCM), integration of bipolar and CMOS technology in this TCM, the design and implementation of a differential current switch bipolar circuit family, integrated programmable memory subsystem design, and extensive use of VLSI technology. The result of these innovations was a 15-ns-cycle air-cooled machine. The salient features and an overview of the machine design are presented.