IBM PS/1

The IBM PS / 1 personal computer IBM tried in 1990, five years after the IBM PCjr a renewed attempt to establish themselves in the home computer market. In September 1994, the PS / 1 was replaced by the IBM Aptiva. All PS/1- and Aptiva models had a built-in modem to access online help and preinstalled software.

Position within the brand IBM

The term "PS / 1" should indicate a limited compared to the professional product line PS / 2 powerful machine. In contrast to the PCjr but the PS / 1 had a higher degree of compatibility with the PS/2-Systemen. The PS/1-Familie was intended for beginners and was sold in normal electronics shops along with comparable offerings from Compaq, Hewlett -Packard, Packard Bell, and others, a departure from the usual strategy that only IBM products, IBM to buy themselves were. All PS/1-Modelle contained a modem, so that the user could request assistance online at IBM. A special feature at all PS/1-Modellen was it that you could revert to the BIOS when both mouse buttons pressed when turning on the computer and thought this let go only after the power-on self-test. For the models 2011 and 2121, this process also led to the fact that the PC-DOS was booted from a built-in ROM instead of the hard disk. In this way the PS/1-Systeme had a basic protection against viruses, as its condition at delivery from the factory had to restore.

During the production of PS/1-Systeme there were different housing:

• 2011 Proprietary design, power supply in the screen
• 2121 Proprietary design, power supply in the screen, one ISA slot
• 2123 based on the IBM PS / 2 Model 30, only a few copies were made
• 2133 desktop model. The two digits 3 refer to the number of available ISA expansion slots and drive bays; CPUs from Intel 80486SX to 80486DX -33 ( sub-model 575 )
• 2155 desktop model. The two digits 5 refer to the number of available expansion slots and drive bays
• 2168 tower model. The numbers 6 and 8 refer to the number of available expansion slots and drive bays

The housing 2133 and 2155 were used in different model years; the tower unit 2168 was not published until later.

" DOS in ROM" models

The original PS / 1 contained a 10 MHz Intel 80286 CPU and was developed with the aim to be easy einzurichtbar and usable. IBM made ​​the rather unusual decision, the motherboard and other electronics in the monitor to accommodate. The early models of 2011 and 2121 started the DOS from a ROM and showed at the beginning of a four-division graphic screen, direct access to help information, Microsoft Works, own software and the DOS command processor bot. It had 1 MB of RAM, a built- in 2400 baud modem, an optional 30 MB hard drive and an optional sound card. IBM also drove a 5.25 " floppy drive, and an Adapter Card Unit ( ACU) to accommodate expansion cards by third parties. Model 2121 used the same chassis as the 2011, but had an ISA expansion slot inside the case. The main memory was a proprietary 4 MB memory module from 2 MB to be extended to 6 MB.

The first PS/1-Modelle (2011, 2121, 2123 ) offered too little expansion opportunities, especially due to lack of ISA expansion slots.

A successor later had an Intel processor with 16 MHz 80386SX, a version with the Intel 80486SX ran at 20 MHz.

The models in 2133 can be divided into the following hardware categories ::

Later models

In May 1993, IBM introduced a " new generation" of PS/1-Produktlinie. These systems contain a normal LPX motherboard. Curiously, many of these later PS/1-Systeme were preloaded with MS -DOS and Microsoft Windows delivered instead with IBM 's PC- DOS or OS / 2 This was because IBM saw the market for OS / 2 in more expensive machines with more processing power. However, one of the first 2133 models had a pre-installed OS / 2 2.1.

End of production

The product line PS / 1 was set in 1994 and replaced by the Aptiva line, which resembled the last PS/1-Modellen of its architecture, but had a market the more common name. Aptivas were sold in the United States until the spring of 2000; then made ​​the price pressure, the product line unprofitable and IBM withdrew completely from the PC consumer market back.