Developers first placed complete microcomputers on cards and packaged them in standard 19-inch racks in the 1970s, soon after the introduction of 8-bit microprocessors.
Arendajad paigutasid mikroprotsessoreid trükkplaatidele ja paigutasid neid standardsetesse 19-tollistesse raamidesse üsna varsti pärast 8-bitiste mikroprotsessorite leiutamist 1970. aastatel.