The IBM PC had long dominated in the business sector. However, their first entry in the home computer market (1984’s Pcjr) was a spectacular failure, and they made a quick exit from the home computer sector.

In 1990, they returned with the Personal System/1, or PS/1 for short. The name is derived from IBM’s previuse (but more powerful) business-oriented line, Personal System/2. However the architecture is closer to that of the older IBM PC/AT. The PS/1 launched with an Intel 286 CPU and PC DOS 4.01, IBM’s branded version of MS-DOS.

We have a later model PS/1 Advisor, with a 25MHz 486SX CPU and 16Mb RAM running Windows 3.11.

This era was the golden age for the Apogee model of shareware distribution, with titles ranging from side-scrollers such as Commander Keen and Duke Nukem to early first-person-shooters including Wolfenstein 3D and Doom.