The IBM Personal Computer, commonly known as the IBM PC, spanned multiple models in its first generation (including the PCjr, the Portable PC, the XT, the AT, the Convertible, and the /370 systems, among others), from 1981 to 1987. It eventually gave way to many splintering product lines after IBM introduced the Personal System/2 in April 1987.
Type | IBM P/N | Date announced | Date withdrawn | Bus |
No. of slots |
No. of bays |
Processor | Clock speed (MHz) |
Stock RAM (KB) |
Maximum RAM (KB) |
FDD | HDD | Notes |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Personal Computer | 5150-001 | August 1981 | Unknown | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 16 KB | 256 KB | none | none | Diskless model; only means of data storage is through IBM Cassette BASIC [1]: 1 |
Personal Computer | 5150-003 | August 1981 | Unknown | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 48 KB | 256 KB | 160 KB | none | Single-sided, double-density floppy disk drive [1]: 1 |
Personal Computer | 5150-013 | Unknown | Unknown | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | August 1981 | Unknown | Unknown | none | |
Personal Computer | 5150-104 | June 1984 | April 1987 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | 256 KB | 360 KB | none | |
Personal Computer | 5150-114 | Unknown | June 1984 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | 256 KB | 160 KB | none | |
Personal Computer | 5150-164 | Unknown | June 1984 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | 256 KB | 360 KB | none | |
Personal Computer | 5150-166 | June 1984 | April 1987 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 256 KB | 256 KB | 360 KB | none | |
Personal Computer | 5150-174 | Unknown | June 1984 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | 256 KB | two 360 KB | none | |
Personal Computer | 5150-176 | June 1984 | April 1987 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 256 KB | 256 KB | two 360 KB | none | |
Personal Computer | 5150-X14 | Unknown | June 1984 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | Unknown | 160 KB | none | Shipped without keyboard |
Personal Computer | 5150-X64 | Unknown | June 1984 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | Unknown | 360 KB | none | Shipped without keyboard |
Personal Computer | 5150-X66 | June 1984 | December 1985 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 256 KB | 256 KB | 360 KB | none | Shipped without keyboard |
Personal Computer | 5150-X74 | Unknown | June 1984 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | Unknown | two 360 KB | none | Shipped without keyboard |
Personal Computer | 5150-X76 | June 1984 | December 1985 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 256 KB | 256 KB | two 360 KB | none | Shipped without keyboard |
PCjr | 4860-004 | November 1983 | Unknown | Custom | N/A | N/A | Intel 8088 | 4.77 | 64 KB | 128 KB | none | none | |
PCjr | 4860-067 | November 1983 | Unknown | Custom | N/A | N/A | Intel 8088 | 4.77 | 128 KB | 128 KB | 360 KB | none | |
Portable Personal Computer | 5155-068 | February 1984 | June 1984 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 512 KB | 360 KB | none | |
Portable Personal Computer | 5155-076 | June 1984 | Unknown | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 512 KB | two 360 KB | none | |
PC Convertible | 5140-002 | April 1986 | Unknown | ISA, 8-bit (proprietary) | N/A | N/A | Intel 8088 | 4.77 | 256 KB | 512 KB | two 720K | none | Application bundle |
PC Convertible | 5140-022 | April 1986 | Unknown | ISA, 8-bit (proprietary) | N/A | N/A | Intel 8088 | 4.77 | 256 KB | 512 KB | two 720K | none | |
Personal Computer XT | 5160-068 | April 1985 | April 1987 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | none | |
Personal Computer XT | 5160-078 | April 1985 | April 1987 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | two 360 KB | none | |
Personal Computer XT | 5160-086 | June 1984 | April 1987 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | 10 MB | |
Personal Computer XT | 5160-087 | March 1983 | June 1984 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 128 KB | 640 KB | 360 KB | 10 MB | |
Personal Computer XT | 5160-088 | April 1986 | Unknown | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 512 KB | 640 KB | 360 KB | 20 MB | |
Personal Computer XT | 5160-089 | April 1986 | June 1987 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 512 KB | 640 KB | 360 KB | 20 MB | Shipped with Enhanced Keyboard |
Personal Computer XT | 5160-267 | April 1986 | Unknown | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | Unknown | |
Personal Computer XT | 5160-277 | April 1986 | Unknown | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | two 360 KB | Unknown | |
Personal Computer XT | 5160-268 | April 1986 | June 1987 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | Unknown | Shipped with Enhanced Keyboard |
Personal Computer XT | 5160-278 | April 1986 | June 1987 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | two 360 KB | Unknown | Shipped with Enhanced Keyboard |
Personal Computer XT/370 | 5160-568 | Unknown | October 1984 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | Unknown | |
Personal Computer XT/370 | 5160-588 | Unknown | October 1984 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | 10 MB | |
Personal Computer XT/370 | 5160-589 | October 1984 | June 1984 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | 10 MB | |
Personal Computer XT Model 286 | 5162-286 | September 1986 | Unknown | ISA, 16-bit | 8 | 2 | Intel 80286 | 6 | 640 KB | 640 KB | 1.2 MB | 20 MB | |
Personal Computer AT | 5170-068 | August 1984 | June 1987 | ISA, 16-bit | 8 | 3 | Intel 80286 | 6 | 256 KB | 512 KB | 1.2 MB | none | |
Personal Computer AT | 5170-099 | August 1984 | April 1987 | ISA, 16-bit | 8 | 3 | Intel 80286 | 6 | 512 KB | 512 KB | 1.2 MB | 20 MB | |
Personal Computer AT | 5170-239 | October 1985 | September 1986 | ISA, 16-bit | 8 | 3 | Intel 80286 | 6 | 512 KB | 512 KB | 1.2 MB | 30 MB | |
Personal Computer AT | 5170-319 | April 1986 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | 8 | 512 KB | 512 KB | 1.2 MB | 30 MB | |
Personal Computer AT | 5170-339 | April 1986 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | 8 | 512 KB | 512 KB | 1.2 MB | 30 MB | Shipped with Enhanced Keyboard |
Personal Computer AT/370 | 5170-599 | October 1984 | April 1987 | ISA, 16-bit | 8 | 3 | Intel 80286 | 6 | 512 KB | 512 KB | 1.2 MB | 20 MB | |
Personal Computer AT/370 | 5170-739 | Unknown | September 1986 | ISA, 16-bit | 8 | 3 | Intel 80286 | Unknown | Unknown | Unknown | Unknown | Unknown | |
Personal Computer AT | 5170-839 | January 1986 | September 1986 | ISA, 16-bit | 8 | 3 | Intel 80286 | Unknown | 512 KB | 512 KB | 1.2 MB | 30 MB | Includes controllers for the IBM 4680 Store System |
Personal Computer AT | 5170-899 | January 1986 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | Unknown | 512 KB | 512 KB | 1.2 MB | 20 MB | Includes controllers for the IBM 4680 Store System |
Personal Computer AT | 5171-168 | October 1986 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | 8 | 512 KB | 512 KB | 1.2 MB | none | Built to TEMPEST specifications |
Personal Computer AT | 5171-339 | October 1986 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | 8 | 512 KB | 512 KB | 1.2 MB | 30 MB | Built to TEMPEST specifications |
3270 PC | 5271-004 | June 1984 | Unknown | ISA, 8-bit | Unknown | Unknown | Intel 8088 | 4.77 | 384 KB | Unknown | Unknown | Unknown | |
3270 PC | 5271-006 | June 1984 | Unknown | ISA, 8-bit | Unknown | Unknown | Intel 8088 | 4.77 | 384 KB | Unknown | Unknown | Unknown | |
Industrial Computer 5531 | 5531-001 | April 1984 | Unknown | ISA, 8-bit | 8 | 3 | Intel 8088 | 4.77 | 128 KB | 640 KB | 360 KB | 10 MB | Industrial version of the IBM PC XT [2] [3] |
Industrial Computer 5531 | 5531-011 | April 1984 | Unknown | ISA, 8-bit | 8 | 3 | Intel 8088 | 4.77 | 256 KB | 640 KB | 1.2 MB | none | Industrial version of the IBM PC XT [2] [3] [4] |
Industrial Computer 5531 | 5531-021 | May 1985 | Unknown | ISA, 8-bit | 8 | 3 | Intel 8088 | 4.77 | 256 KB | 640 KB | 1.2 MB | 20 MB | Industrial version of the IBM PC XT [2] [3] |
7531 Industrial Computer | 7531-041 | May 1985 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | 6 | 512 KB | 1 MB | Unknown | Unknown | Industrial version of the IBM PC AT, tower form-factor |
7532 Industrial Computer | 7532-041 | May 1985 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | 6 | 512 KB | 1 MB | Unknown | Unknown | Industrial version of the IBM PC AT, 19-inch rack-mountable form factor |
Industrial Computer 7552 | 7552-040 | October 1986 | Unknown |
ISA, 16-bit MCA, 16-bit (undocumented) |
8 (modules, 7 fillable) | 3 (as modules) | Intel 80286 | 10 | 4 MB | Unknown | none | none | Also known as "Gearbox", rack-mountable ruggedized modular industrial computer, hybrid MCA and ISA with compromised ISA signal lines—notable for introducing the (16-bit) Micro Channel architecture half a year before the announcement of the PS/2 line in April 1987 [5] [6] [7] [8] |
Industrial Computer 7552 | 7552-140 | October 1986 | Unknown |
ISA, 16-bit MCA, 16-bit (undocumented) |
8 (modules, 7 fillable) | 3 (as modules) | Intel 80286 | 10 | 4 MB | Unknown | one 1.44 MB (as a module) | 20 MB (as a module, 40 MB as two identical modules) | Also known as "Gearbox", rack-mountable ruggedized modular industrial computer, hybrid MCA and ISA with compromised ISA signal lines—notable for introducing the (16-bit) Micro Channel architecture half a year before the announcement of the PS/2 line in April 1987 [5] [6] [7] [8] |
Timeline of the IBM Personal Computer |
---|
Asterisk (*) denotes a model released in Japan only |
IBM doesn't advertise the PS/2 as a factory-floor machine, yet the PS/2's backplane bus structure, Micro Channel, appeared in a factory-floor computer before the PS/2 itself came on the market. People who examined the IBM 7552 Gearbox, ostensibly a factory-hardened version of the AT, notice something odd about the unit's bus: It had more bus lines than could be accounted for by the AT bus. The extra lines turned out to be the 16-bit Micro Channel. Nobody at IBM said anything about it at the time, because PS/2 hadn't yet been introduced.
The IBM Personal Computer, commonly known as the IBM PC, spanned multiple models in its first generation (including the PCjr, the Portable PC, the XT, the AT, the Convertible, and the /370 systems, among others), from 1981 to 1987. It eventually gave way to many splintering product lines after IBM introduced the Personal System/2 in April 1987.
Type | IBM P/N | Date announced | Date withdrawn | Bus |
No. of slots |
No. of bays |
Processor | Clock speed (MHz) |
Stock RAM (KB) |
Maximum RAM (KB) |
FDD | HDD | Notes |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Personal Computer | 5150-001 | August 1981 | Unknown | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 16 KB | 256 KB | none | none | Diskless model; only means of data storage is through IBM Cassette BASIC [1]: 1 |
Personal Computer | 5150-003 | August 1981 | Unknown | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 48 KB | 256 KB | 160 KB | none | Single-sided, double-density floppy disk drive [1]: 1 |
Personal Computer | 5150-013 | Unknown | Unknown | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | August 1981 | Unknown | Unknown | none | |
Personal Computer | 5150-104 | June 1984 | April 1987 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | 256 KB | 360 KB | none | |
Personal Computer | 5150-114 | Unknown | June 1984 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | 256 KB | 160 KB | none | |
Personal Computer | 5150-164 | Unknown | June 1984 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | 256 KB | 360 KB | none | |
Personal Computer | 5150-166 | June 1984 | April 1987 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 256 KB | 256 KB | 360 KB | none | |
Personal Computer | 5150-174 | Unknown | June 1984 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | 256 KB | two 360 KB | none | |
Personal Computer | 5150-176 | June 1984 | April 1987 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 256 KB | 256 KB | two 360 KB | none | |
Personal Computer | 5150-X14 | Unknown | June 1984 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | Unknown | 160 KB | none | Shipped without keyboard |
Personal Computer | 5150-X64 | Unknown | June 1984 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | Unknown | 360 KB | none | Shipped without keyboard |
Personal Computer | 5150-X66 | June 1984 | December 1985 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 256 KB | 256 KB | 360 KB | none | Shipped without keyboard |
Personal Computer | 5150-X74 | Unknown | June 1984 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 64 KB | Unknown | two 360 KB | none | Shipped without keyboard |
Personal Computer | 5150-X76 | June 1984 | December 1985 | ISA, 8-bit | 5 | 2 | Intel 8088 | 4.77 | 256 KB | 256 KB | two 360 KB | none | Shipped without keyboard |
PCjr | 4860-004 | November 1983 | Unknown | Custom | N/A | N/A | Intel 8088 | 4.77 | 64 KB | 128 KB | none | none | |
PCjr | 4860-067 | November 1983 | Unknown | Custom | N/A | N/A | Intel 8088 | 4.77 | 128 KB | 128 KB | 360 KB | none | |
Portable Personal Computer | 5155-068 | February 1984 | June 1984 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 512 KB | 360 KB | none | |
Portable Personal Computer | 5155-076 | June 1984 | Unknown | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 512 KB | two 360 KB | none | |
PC Convertible | 5140-002 | April 1986 | Unknown | ISA, 8-bit (proprietary) | N/A | N/A | Intel 8088 | 4.77 | 256 KB | 512 KB | two 720K | none | Application bundle |
PC Convertible | 5140-022 | April 1986 | Unknown | ISA, 8-bit (proprietary) | N/A | N/A | Intel 8088 | 4.77 | 256 KB | 512 KB | two 720K | none | |
Personal Computer XT | 5160-068 | April 1985 | April 1987 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | none | |
Personal Computer XT | 5160-078 | April 1985 | April 1987 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | two 360 KB | none | |
Personal Computer XT | 5160-086 | June 1984 | April 1987 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | 10 MB | |
Personal Computer XT | 5160-087 | March 1983 | June 1984 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 128 KB | 640 KB | 360 KB | 10 MB | |
Personal Computer XT | 5160-088 | April 1986 | Unknown | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 512 KB | 640 KB | 360 KB | 20 MB | |
Personal Computer XT | 5160-089 | April 1986 | June 1987 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 512 KB | 640 KB | 360 KB | 20 MB | Shipped with Enhanced Keyboard |
Personal Computer XT | 5160-267 | April 1986 | Unknown | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | Unknown | |
Personal Computer XT | 5160-277 | April 1986 | Unknown | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | two 360 KB | Unknown | |
Personal Computer XT | 5160-268 | April 1986 | June 1987 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | Unknown | Shipped with Enhanced Keyboard |
Personal Computer XT | 5160-278 | April 1986 | June 1987 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | two 360 KB | Unknown | Shipped with Enhanced Keyboard |
Personal Computer XT/370 | 5160-568 | Unknown | October 1984 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | Unknown | |
Personal Computer XT/370 | 5160-588 | Unknown | October 1984 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | 10 MB | |
Personal Computer XT/370 | 5160-589 | October 1984 | June 1984 | ISA, 8-bit | 8 | 2 | Intel 8088 | 4.77 | 256 KB | 640 KB | 360 KB | 10 MB | |
Personal Computer XT Model 286 | 5162-286 | September 1986 | Unknown | ISA, 16-bit | 8 | 2 | Intel 80286 | 6 | 640 KB | 640 KB | 1.2 MB | 20 MB | |
Personal Computer AT | 5170-068 | August 1984 | June 1987 | ISA, 16-bit | 8 | 3 | Intel 80286 | 6 | 256 KB | 512 KB | 1.2 MB | none | |
Personal Computer AT | 5170-099 | August 1984 | April 1987 | ISA, 16-bit | 8 | 3 | Intel 80286 | 6 | 512 KB | 512 KB | 1.2 MB | 20 MB | |
Personal Computer AT | 5170-239 | October 1985 | September 1986 | ISA, 16-bit | 8 | 3 | Intel 80286 | 6 | 512 KB | 512 KB | 1.2 MB | 30 MB | |
Personal Computer AT | 5170-319 | April 1986 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | 8 | 512 KB | 512 KB | 1.2 MB | 30 MB | |
Personal Computer AT | 5170-339 | April 1986 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | 8 | 512 KB | 512 KB | 1.2 MB | 30 MB | Shipped with Enhanced Keyboard |
Personal Computer AT/370 | 5170-599 | October 1984 | April 1987 | ISA, 16-bit | 8 | 3 | Intel 80286 | 6 | 512 KB | 512 KB | 1.2 MB | 20 MB | |
Personal Computer AT/370 | 5170-739 | Unknown | September 1986 | ISA, 16-bit | 8 | 3 | Intel 80286 | Unknown | Unknown | Unknown | Unknown | Unknown | |
Personal Computer AT | 5170-839 | January 1986 | September 1986 | ISA, 16-bit | 8 | 3 | Intel 80286 | Unknown | 512 KB | 512 KB | 1.2 MB | 30 MB | Includes controllers for the IBM 4680 Store System |
Personal Computer AT | 5170-899 | January 1986 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | Unknown | 512 KB | 512 KB | 1.2 MB | 20 MB | Includes controllers for the IBM 4680 Store System |
Personal Computer AT | 5171-168 | October 1986 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | 8 | 512 KB | 512 KB | 1.2 MB | none | Built to TEMPEST specifications |
Personal Computer AT | 5171-339 | October 1986 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | 8 | 512 KB | 512 KB | 1.2 MB | 30 MB | Built to TEMPEST specifications |
3270 PC | 5271-004 | June 1984 | Unknown | ISA, 8-bit | Unknown | Unknown | Intel 8088 | 4.77 | 384 KB | Unknown | Unknown | Unknown | |
3270 PC | 5271-006 | June 1984 | Unknown | ISA, 8-bit | Unknown | Unknown | Intel 8088 | 4.77 | 384 KB | Unknown | Unknown | Unknown | |
Industrial Computer 5531 | 5531-001 | April 1984 | Unknown | ISA, 8-bit | 8 | 3 | Intel 8088 | 4.77 | 128 KB | 640 KB | 360 KB | 10 MB | Industrial version of the IBM PC XT [2] [3] |
Industrial Computer 5531 | 5531-011 | April 1984 | Unknown | ISA, 8-bit | 8 | 3 | Intel 8088 | 4.77 | 256 KB | 640 KB | 1.2 MB | none | Industrial version of the IBM PC XT [2] [3] [4] |
Industrial Computer 5531 | 5531-021 | May 1985 | Unknown | ISA, 8-bit | 8 | 3 | Intel 8088 | 4.77 | 256 KB | 640 KB | 1.2 MB | 20 MB | Industrial version of the IBM PC XT [2] [3] |
7531 Industrial Computer | 7531-041 | May 1985 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | 6 | 512 KB | 1 MB | Unknown | Unknown | Industrial version of the IBM PC AT, tower form-factor |
7532 Industrial Computer | 7532-041 | May 1985 | Unknown | ISA, 16-bit | 8 | 3 | Intel 80286 | 6 | 512 KB | 1 MB | Unknown | Unknown | Industrial version of the IBM PC AT, 19-inch rack-mountable form factor |
Industrial Computer 7552 | 7552-040 | October 1986 | Unknown |
ISA, 16-bit MCA, 16-bit (undocumented) |
8 (modules, 7 fillable) | 3 (as modules) | Intel 80286 | 10 | 4 MB | Unknown | none | none | Also known as "Gearbox", rack-mountable ruggedized modular industrial computer, hybrid MCA and ISA with compromised ISA signal lines—notable for introducing the (16-bit) Micro Channel architecture half a year before the announcement of the PS/2 line in April 1987 [5] [6] [7] [8] |
Industrial Computer 7552 | 7552-140 | October 1986 | Unknown |
ISA, 16-bit MCA, 16-bit (undocumented) |
8 (modules, 7 fillable) | 3 (as modules) | Intel 80286 | 10 | 4 MB | Unknown | one 1.44 MB (as a module) | 20 MB (as a module, 40 MB as two identical modules) | Also known as "Gearbox", rack-mountable ruggedized modular industrial computer, hybrid MCA and ISA with compromised ISA signal lines—notable for introducing the (16-bit) Micro Channel architecture half a year before the announcement of the PS/2 line in April 1987 [5] [6] [7] [8] |
Timeline of the IBM Personal Computer |
---|
Asterisk (*) denotes a model released in Japan only |
IBM doesn't advertise the PS/2 as a factory-floor machine, yet the PS/2's backplane bus structure, Micro Channel, appeared in a factory-floor computer before the PS/2 itself came on the market. People who examined the IBM 7552 Gearbox, ostensibly a factory-hardened version of the AT, notice something odd about the unit's bus: It had more bus lines than could be accounted for by the AT bus. The extra lines turned out to be the 16-bit Micro Channel. Nobody at IBM said anything about it at the time, because PS/2 hadn't yet been introduced.