IBM PS/1 - Position in IBM's PC Brands

Position in IBM's PC Brands

Like the PCjr, the PS/1's name suggested a more limited machine than IBM's business line, the PS/2. However, unlike the PS/2, the PS/1 was based upon architecture closer to the AT and compatibles, such as using ISA, plain VGA, and IDE. The PS/1 line was created for new computer users and was sold in consumer electronics stores alongside comparable offerings from Compaq, Hewlett-Packard, Packard Bell, and others. All PS/1 models came with a modem installed so users could access online IBM help services, which were provided by partnerships with Prodigy and Quantum. Although the first models used custom designed components and design, later desktop and tower models used mostly standard components. The earlier models included a ROM with IBM's PC-DOS and a graphical shell, however the system was compatible with other DOS implementations and the shell could be installed on the hard-drive. Later models included a feature called "Rapid Resume" which gave the computers the ability to go into standby mode as well as a hibernation function. There were several form factors used during the PS/1's production:

• 2011 Proprietary design, power supply is within CRT
• 2121 Proprietary design, power supply is within CRT, up to two available ISA slots
• 2123 Limited production model. Based on IBM PS/2 model 30 case.
• 2133 Desktop case. The 3x3 references the available slots and drive bays.
• 2155 Desktop case larger than 2133. The 5x5 references the available slots and drive bays.
• 2168 Tower unit. The 6x8 references the available slots and bays.

The 2133 and 2155 cases were used in several model years with the 2168 tower unit appearing a bit later.