IBM PS/1

IBM PS/1 (model 2011)
Release date 1990
Operating system PC-DOS 4.01 (in ROM)
CPU Intel 80286 @ 10 MHz
Memory 512 KB ~ 1 MB
IBM PS/1 (model 2121)
Release date 1992
Discontinued 1993
Operating system PC-DOS 4.01 in ROM)
CPU Intel 80386SX @ 16 MHz
Memory 2 MB ~ 6 MB
IBM PS/1 (model 2133)
Release date 1992
Discontinued 1993
Operating system PC-DOS 4.01
CPU Intel 80386SX @ 25 MHz or 80486SX @ 20 MHz or 80486SX @ 25 MHz
Memory 2 MB ~ 16 MB (2-4MB on-board)
IBM PS/1 (model 2155)
Operating system IBM-DOS / Windows 3.1
CPU Intel 80486SX @ 25 MHz
Memory 2 MB ~ 6 MB

The IBM PS/1 was a brand for a line of personal computers and was IBM's return to the home market in 1990, five years after the IBM PCjr. It was replaced by the IBM Aptiva in September 1994.

Contents

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:

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

Models 2011 and 2121

The original PS/1, based on a 10 MHz Intel 80286 CPU, was designed to be easy to set up and use. It featured 1 MB of memory, built-in modem, an optional 30 MB hard disk. IBM also released a 5.25" disk drive unit and an Adapter Card Unit (ACU) to install third-party expansion cards. Some of the lower end PS/1 models suffered from very limited expansion capabilities, since they lacked standard ISA expansion slots.

The 2121 series computers used the same form factor as the 2011 series, but included up to two ISA slots inside the case. Memory could be expanded from 2MiB to 6MiB using a proprietary 4 MiB memory module. The higher-end 2121 featured an Intel 80386SX processor running at 16 MHz. Similar to a few Tandy 1000 models, the early PS/1's had an operating system (PC-DOS 4.01) built in to ROM, rather than loading it from a hard drive. It was possible to have the computer boot from the hard drive if the operating system was upgraded.

Monitors IBM made the decision to put the DC power supply in the monitor, making use of third-party monitors difficult and essentially impractical and limiting the usefulness of the computer if the monitor needed service (similar to the problems of the Coleco Adam years earlier). Some models were sold with greyscale VGA monitors.

"DOS in ROM" The early 2011 and 2121 series would boot up off the DOS in ROM and load a "4-quad" screen which allowed users to access help, rapidly launch pre-installed software, connect online, and access files on the hard drive.

Model 2133

The 2133 series PS/1 computers can be split into the following major hardware categories[1][2]:

Model MB FRU CPU RAM VRAM SIMM Hard-Drive
2133-?11 93F2397 Intel 80386sx @ 25 MHz 2 MB 256KB 2x72 Pin FPM 59G9567 (85 MB IDE)
2133-?13 93F2397 Intel 80386sx @ 25 MHz 2 MB 256KB 2x72 Pin FPM 93F2329 (129 MB IDE)
2133-?43 34G1885 Intel 80486sx @ 20 MHz 4 MB 512KB 2x30 Pin FPM 93F2329 (129 MB IDE)
2133-?50 34G1848 Intel 80486sx @ 25 MHz 4 MB 512KB 2x30 Pin FPM 93F2329 (129 MB IDE)
2133-?53 34G1848 Intel 80486sx @ 25 MHz 4 MB 512KB 2x30 Pin FPM 93F2329 (129 MB IDE)

Post "DOS in ROM" models

On May 11, 1993 IBM introduced a "new generation" of the PS/1 line.[1] Later PS/1s featured standard LPX-architecture motherboard. Many of these later PS/1s shipped from the factory with MS-DOS and Microsoft Windows, rather than IBM's PC-DOS and/or OS/2. An early 2133 model did come preloaded with OS/2 2.1. This was because IBM targeted OS/2 for high-end computing machines with more power.

Discontinuation

The PS/1 line was discontinued in 1994 and replaced with the Aptiva line, which was architecturally very similar to the later models of the PS/1, but with a more marketing-friendly name. Aptivas were sold in the United States until early 2000, when price pressures made the line unprofitable and IBM withdrew from the retail desktop PC market entirely.

See also

References

  1. ^ "PS/1 - 2133 18A/21C/23C/52D (SL-B) Service parts". IBM. 1999-03-08. http://ps-2.kev009.com:8081/pcpartnerinfo/ctstips/50fa.htm. Retrieved 2008-06-14. 
  2. ^ Hardware Maintenance Service for PS1 computer (Machine Types 2133, 2155, and 2168). IBM Corporation. March 1993. 63G2028 .

External links

Preceded by
IBM PCjr
IBM Personal Computers Succeeded by
IBM Aptiva