year 1990

The IBM PS/1 personal computer was IBM’s return to the home market in 1990, five years after the IBM PCjr. The original PS/1, based on a 10 MHz Intel 80286 CPU, was designed to be easy to set up and use. Like many Tandy 1000 models, it had DOS 4.01 built in to ROM, but it made the unusual decision to put the power supply for the entire unit in the monitor, making use of third-party monitors impossible and limiting the usefulness of the computer if the monitor needed service.