IBM 5100 Portable Computer

Weighing approximately 50 pounds and sized slightly larger than an IBM typewriter, the 5100 Portable Computer was announced by the company's General Systems Division (GSD) in September 1975. The Portable Computer was intended to put computer capabilities at the fingertips of engineers, analysts, statisticians and other problem-solvers. Available in 12 models providing 16K, 32K, 48K or 64K positions of main storage, the 5100 sold for between $8,975 and $19,975. The 5100 was available with either APL or BASIC or both programming languages.

If the size and weight of the 5100 seems huge by today's standards, then the Portable Computer was very slender compared to a late-1960's IBM computer with the equivalent capability. Such a machine would have been nearly as large as two desks and would have weighed about half a ton.

IBM offered three Problem-Solver Libraries, contained in magnetic tape cartridges (shown above), with the IBM 5100 to provide more than 100 interactive routines applicable to mathematical problems, statistical techniques and financial analyses. The cartridge had a 204,000-character capacity on 300 feet of 1/4-inch tape. The 5100 Portable Computer was withdrawn from marketing in March 1982.

IBM Archives > Exhibits > IBM Personal Computer
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