The following is the text of an IBM Data Processing Division press release distributed on June 18, 1959.
Double capacity magnetic drum storage for the IBM 650 data processing system, the most widely used commercial and engineering computer in the world, was announced today by International Business Machines Corporation's Data Processing Division. Providing 40,000 memory positions for storing data and operating instructions in the form of 4,000 ten-digit words, the increased capacity drum is featured in the new Model 4 IBM 650 console unit.
The double capacity drum enables the 650 to handle applications requiring greater storage than the 20,000-digit, or 2,000 ten-digit word, capacity provided by the magnetic drum in the Model 2 console. The additional capacity also expands the 650's "table look-up" operation which facilitates the automatic searching of rate tables as used in the insurance, public utility, transportation and other commercial fields. The need for multiple passes of data through the computer or for peripheral punched card operations, such as sorting and collating is substantially reduced as a result of the new console's ability to accommodate twice the volume of stored data.
Increased memory capacity of the Model 4 IBM 650 console has been achieved with the same size drum as used in the Model 2 console by doubling the number of locations used for recording data in the form of magnetic spots on the surface of the drum. The new console utilizes the same programming techniques, operation codes and input-output storage areas as the Model 2 unit. The 650's calculating speeds and its average access time of 2.4 thousandths of a second to data stored on the drum remain unchanged with the new console.
The Model 4 console with double capacity drum is designed for use with the three major types of IBM 650 data processing systems - - the basic or card system, the 650 with magnetic tapes, and the IBM RAMAC 650 with random access disk storage. A Model 2 console with its 20,000-digit drum may be converted to a Model 4 console and 40,000-digit drum at the 650 installation site.
The purchase price for the Model 4 IBM 650 console is $150,000. The monthly rental charge is $3,250. The Model 2 console continues to rent for $2,400 a month and to sell for $1l5,000.