IBM PS/2 Model 80

The IBM PS/2 Model 80 (IBM machine type 8580) was IBM's flagship Intel 80386DX-based floor-standing tower in the IBM Personal System/2 family, introduced in April 1987 with the rest of the PS/2 line. It paired a full 32-bit Micro Channel Architecture implementation with a tower chassis built for expansion, eight MCA slots, large ESDI drives and a 225 W PSU. The Model 80 is the tower counterpart to the IBM PS/2 Model 70 desktop and was IBM's primary platform for OS/2, AIX PS/2 and Novell NetWare deployments through the late 1980s and into the early 1990s.

IBM Personal System/2 Model 80

IBM PS/2 Model 80 (8580) floor-standing tower
Specifications
Developer	IBM Entry Systems Division, Boca Raton
Manufacturer	IBM
Type	Floor-standing tower personal computer / server
Released	April 2, 1987
Discontinued	c. 1993
CPU	Intel 80386DX @ 16 MHz (8580-041 / 071); 20 MHz (8580-111 / 311); 25 MHz (8580-A21 / A31). Optional Intel 80387DX coprocessor in adjacent planar socket
Memory	1–4 MB stock (submodel-dependent); 4 × 72-pin proprietary PS/2 SIMM sockets on planar; 16 MB max on planar; further expansion via MCA Memory Adapter cards
Storage	1.44 MB 3.5" diskette + ESDI hard drive: 44 MB (8580-041); 70 MB (8580-071); 115 MB (8580-111 / A21); 314 MB (8580-311 / A31) via IBM ESDI Fixed Disk Adapter/A
Display	Integrated VGA on planar (256 KB VRAM, 15-pin DSUB); supports IBM 8503 / 8512 / 8513 / 8514 displays
Sound	PC speaker
Dimensions	597 H × 166 W × 482 D mm
Weight	~21.3 kg (heavier with 314 MB drive)
OS / Firmware	IBM PC DOS 3.30 / 4.00 / 5.00; IBM OS/2 1.x / 2.x / Warp 3; IBM AIX PS/2; Novell NetWare 2.x / 3.x; Windows 3.0 / 3.1
Predecessor	IBM PS/2 Model 60 (286-class tower sibling)
Successor	IBM PS/2 Model 90 XP 486 / Model 95 XP 486
Model no.	8580

The Model 80 chassis is the same tower used by the IBM PS/2 Model 60; the Model 80 differs from the Model 60 in the planar (32-bit MCA, 80386DX, on-planar VGA, larger ESDI drives). Restoration considerations between Model 60 and Model 80 differ mainly in the planar — the Model 80 planar is afflicted by the same surface-mount aluminium electrolyte leakage that defines the IBM PS/2 Model 70 failure mode.

Submodels

Model 80 submodels

Submodel	CPU	Speed	HDD	Notes
8580-041	80386DX	16 MHz	44 MB ESDI	Early submodel, April 1987 launch
8580-071	80386DX	16 MHz	70 MB ESDI	16 MHz with larger ESDI
8580-111	80386DX	20 MHz	115 MB ESDI	20 MHz, 115 MB ESDI (Type 1 planar)
8580-311	80386DX	20 MHz	314 MB ESDI	20 MHz, 314 MB ESDI (server config)
8580-A21	80386DX	25 MHz	115 MB ESDI	25 MHz top-end (Type 2 planar)
8580-A31	80386DX	25 MHz	314 MB ESDI	25 MHz, 314 MB ESDI (server config)

The planar revisions split into Type 1 (16 / 20 MHz, original 1987 design) and Type 2 (25 MHz, later design). Type 2 planars have a different memory subsystem and require Type 2-specific Reference Diskettes and SIMMs.

Chassis and Layout

The Model 80 chassis is the floor-standing tower introduced with the Model 60:

• Height × width × depth: approx 591 × 165 × 480 mm.
• Weight (configured): approx 21.3 kg.
• Two side panels on the tower; the larger side panel (left, when looking at the front) gives access to the MCA riser and planar.
• Eight MCA slots on a vertical riser: 1 × 8-bit + 7 × 32-bit.
• Four drive bays stacked vertically in the front of the tower:

  Top bay: 5.25" full-height (tape backup or second 5.25" device).

  Bay 2: 3.5" half-height (1.44 MB floppy).

  Bay 3: 3.5" half-height (ESDI hard drive).

  Bay 4: 3.5" half-height (spare or second hard drive on server configs).

• PSU: 225 W at the top of the chassis (above the drive cage). Same PSU rating as the 8560-071.
• Planar mounts on the floor of the chassis.

Planar

The Model 80 planar carries:

• CPU: 80386DX, PGA-132, socketed. 16, 20 or 25 MHz depending on submodel.
• Optional 80387DX coprocessor in a socket adjacent to the 80386DX.
• Memory: 4 × 72-pin SIMM sockets accepting 1, 2 or 4 MB modules. Maximum 16 MB (4 × 4 MB) on planar. Up to 64 MB system memory with MCA Memory Adapter cards. PS/2 72-pin SIMMs are proprietary to IBM PS/2.
• RTC: Dallas DS1287 / DS12887 (24-pin DIP marked "DALLAS") with integrated lithium cell.
• Onboard VGA: IBM VGA implementation with 256 KB of dedicated VRAM. Same VGA implementation as the Model 70.
• MCA bus controller: 32-bit MCA implementation providing one 8-bit and seven 32-bit slots.
• Floppy controller integrated on the planar.
• Surface-mount aluminium electrolytic capacitors for IC bypassing throughout the planar — the same SMD electrolytics that leak on the Model 70.

SMD Electrolyte Leakage

The Model 80 planar (along with the Model 70 planar) is the source of the famous PS/2 plague. Surface-mount aluminium electrolytic capacitors — 10 µF / 16 V and 47 µF / 16 V — leak after 30+ years and produce progressive corrosion of the planar's traces and IC pins.

Symptoms:

• Brown / green residue near a SMD cap base.
• Crusty deposits on nearby PCB traces.
• Intermittent POST faults; system passes POST cold but fails when warm.
• Random reboots.
• Specific functional area (onboard VGA, RTC, serial, ESDI controller) becomes intermittent.
• Eventually, planar dies completely.

The Model 80 planar typically carries 40–50 SMD electrolytics (more than the Model 70 because of the additional MCA slot count and server-class memory subsystem). Full recap is a substantial undertaking — see IBM PS/2 Model 80 Capacitor Replacement Guide.

Display

Like the Model 70, the Model 80 has VGA on the planar. The VGA chip and 256 KB of dedicated VRAM are on the planar; no display adapter card is required.

For higher resolution, the IBM 8514/A MCA display adapter card provides 1024 × 768 with a matching IBM 8514 16" display.

Drive Architecture

The Model 80 uses the PS/2 single-cable drive interface for the floppy drive and the IBM ESDI Fixed Disk Adapter/A for the hard drive. The 8580 server configurations (-311, -A31) accept two ESDI drives — primary in Bay 3, secondary in Bay 4.

ESDI drives in the 8580:

• 44 MB — 8580-041, 16 MHz submodel.
• 70 MB — 8580-071, 16 MHz submodel.
• 115 MB — 8580-111, 8580-A21.
• 314 MB — 8580-311, 8580-A31 (server configurations).

The 314 MB ESDI drive is a full-height 5.25" form factor and requires the top drive bay; on the 8580-311 / A31 the top drive bay is occupied by the 314 MB drive and is not available for a 5.25" tape backup unit.

Reference Diskette

The Model 80 requires a Model 80-specific Reference Diskette. The Type 1 planar (8580-041 / 071 / 111 / 311) uses one Reference Diskette image; the Type 2 planar (8580-A21 / A31) uses a different Reference Diskette image with extensions for the 25 MHz memory subsystem. Reference Diskettes are not cross-compatible between Type 1 and Type 2 planars.

Used for:

• SETUP (drive types, date, time, memory size).
• MCA Auto Configuration.
• Advanced Diagnostics (Ctrl-A from Reference Diskette menu).
• Reading and writing CMOS configuration.

Software

• PC DOS 3.30 / 4.00 / 5.00 — the contemporary DOS releases.
• OS/2 1.x (and IBM's later OS/2 2.0 / 2.1 / Warp 3) — the Model 80 was IBM's premier OS/2 platform for several years.
• AIX PS/2 — IBM's Unix for PS/2.
• Novell NetWare 2.x / 3.x — the Model 80 tower with ESDI drives was a common NetWare server platform.
• Windows 3.0 / 3.1 run on DOS on the Model 80.

Common Faults

• SMD electrolytic leakage on the planar. Most common Model 80 failure. See IBM PS/2 Model 80 Capacitor Replacement Guide.
• Dead DS1287 / DS12887 RTC battery producing the 161 / 162 / 163 POST cluster. See IBM PS/2 Model 80 Maintenance Guide.
• ESDI controller cap failure producing 10455 / 10463 errors. See IBM PS/2 Model 80 Capacitor Replacement Guide.
• Drive stiction on long-stored ESDI drives, especially the 314 MB drives.
• 165 card-ID-mismatch after MCA card change without Auto Configuration. The Model 80's 7 × 32-bit MCA slots mean more cards in the system and a higher 165 rate than the Model 70.
• Failed PSU electrolytics (225 W PSU). See IBM PS/2 Model 80 Capacitor Replacement Guide.

Specifications Summary

Model 80 stock specifications

Spec	041	071	111	311	A21	A31
CPU	80386DX-16	80386DX-16	80386DX-20	80386DX-20	80386DX-25	80386DX-25
RAM stock	1 MB	2 MB	2 MB	4 MB	4 MB	4 MB
RAM max on planar	16 MB	16 MB	16 MB	16 MB	16 MB	16 MB
FDD	1.44 MB 3.5"	1.44 MB 3.5"	1.44 MB 3.5"	1.44 MB 3.5"	1.44 MB 3.5"	1.44 MB 3.5"
HDD	44 MB ESDI	70 MB ESDI	115 MB ESDI	314 MB ESDI	115 MB ESDI	314 MB ESDI
Coprocessor	80387DX (opt.)	80387DX (opt.)	80387DX (opt.)	80387DX (opt.)	80387DX (opt.)	80387DX (opt.)
Video	Onboard VGA	Onboard VGA	Onboard VGA	Onboard VGA	Onboard VGA	Onboard VGA
PSU	225 W	225 W	225 W	225 W	225 W	225 W
MCA slots	8 (1 × 8-bit, 7 × 32-bit)	8	8	8	8	8
Bays	4	4	4	4 (top occupied by 314 MB drive)	4	4 (top occupied by 314 MB drive)
Planar type	Type 1	Type 1	Type 1	Type 1	Type 2	Type 2

Pricing

Launch pricing (April 1987):

• 8580-041: $6,995 USD.
• 8580-071: $8,495 USD.
• 8580-111: $10,995 USD.

These were 1987 prices for high-end IBM business towers. The Model 80 was IBM's flagship PS/2 system and was priced accordingly. Server configurations (-311, -A31) commanded substantial premiums above these base prices.

Gallery

• 
  IBM PS/2 Model 80 (8580) floor-standing tower
• 
  Front-bezel "Model 80 386" badge

Related Pages

• IBM PS/2 Model 80 Maintenance Guide
• IBM PS/2 Model 80 Troubleshooting Guide
• IBM PS/2 Model 80 Capacitor Replacement Guide
• IBM PS/2 Model 60 — tower sibling (286-class)
• IBM PS/2 Model 70 — desktop sibling (386-class)

References

• IBM PS/2 Model 80 — Ardent Tool Quick Reference. FRU breakdown, submodel matrix, planar Type 1 vs Type 2 distinction.
• IBM PS/2 Model 80 — Wikipedia. Source for release date (April 1987), tower chassis details, OS/2 / NetWare deployment history.
• IBM PS/2 Model 80 — DOS Days. Source for the 225 W PSU rating, ESDI controller, on-planar VGA, RAM SIMM topology, planar Type 1 vs Type 2.
• Commonly Failing Electronic Components, minuszerodegrees.net.
• IBM, IBM Personal System/2 Hardware Maintenance Manual (S52G-9971-02, October 1994).