Rebuilding the Office around the Mainframe: IBM’s S/360 in Context

The Oxford English Dictionary states that originally, a mainframe only defined the central processing unit and primary memory of a computer, whereas now a mainframe describes any large or general-purpose computer, specifically supporting numerous peripherals or subordinate computers. The IBM System/360, announced in 1964 and first installed at around 1967, consists of a collection of peripherals that can be connected to any central processing unit in the system family. Due to the size of both the individual components and the entire system, the design and layout of the office often needed to accommodate for the machine. Furthermore, “the experiences of weight, surface texture, sound and smell are part of the physicality of object” (Dannehl 2013, 130) so in order to experience the environment of a designated computer room, several museums have reconstructed at least some of the structure of a computer room. At the Living Computers Museum+Labs in Seattle the entrance to the separately airconditioned room is up a ramp, because of the raised floor that supports the weight of the computer and hides the very thick cables. Purchasing and installing an IBM System/360 required careful planning in terms of physical requirements and site selection, taking into account environmental, electrical, and signal factors. Besides the system and associated personnel, other furniture including storage cabinets, work tables, chairs, and desks also influenced planning. Furthermore, the length of the cables connecting the machines limited the distance between the system components. The schedule proposed by IBM encouraged customers to order six months before delivery and finalizing the layout two months later to allow for building alterations and time to process the cable order (IBM, 1975). Once the machine was installed, the dimensions and layout continuously influenced the workflow and working conditions of the users.

Dannehl, Karin. 2013. “Object biographies. From production to consumption.” In History and Material Culture: A Student’s Guide to Approaching Alternative Sources, edited by Harvey, Karen, 123-138. Routledge.

IBM System/360 Model 20 Installation Manual-Physical Planning. Systems Reference Library. Atlanta, Georgia: International Business Machines Corporation, 1975. Living Computers Museum+Labs, IBM, Box 1, 76027.