Model 5560

General Information
5560 Planar
Model Types
SCSI Adapters
Inner View

PS/55 Processor Complexes
   W0 Complex
   W1/2 Complex
   N Complex / DX2-66 Upgrade Type-B
CPU Upgrades
Complex Upgrades

Content created by Sandy. Edited by Major Tom.

General Information

5560-W was the first desktop model with 486 class CPU. It was introduced to the market on Oct. 1990 together with 5580-Y.

5560 is based on PS/2 Model 90 (8590 or 9590). It uses a similar, but not identical chassis. The planar has been redesigned, so were some of the processor boards. The main differences are:

  • 5560 doesn't use memory riser cards
  • Two extra 32-bit MCA slots in place of the memory riser connectors
  • SIMM sockets are located directly on the planar
  • No XGA video on the planar
  • Power connectors are not Edge Card type
  • The second serial port is missing

Photo of the system unit (5560-W1B with "kit W2B")

Also sold by RICOH as PS Model 5560-W.

5560 Planar (79F5496, shared by all 5560 systems)

J1 Serial port
J2 Parallel port
J3 Mouse port
J4 Keyboard port
J5 Processor complex connector
J6 Power on pass word
J7 32-bit MCA slot with BVE
J8 32-bit MCA slot with AVE
J9/J10 32-bit MCA slot
J11/J12 32-bit MCA slot
J13/J23 Power Supply connector
J24 FDD connector
J26/J27 DBA ESDI solder pads
J28 Front Panel connector
J30 Fan connector
Y1 40.00 MHz Osc (planar I/O bus?)
Y2 22.1148 MHz Osc (UART)
Y4 14.318 MHz Osc (adapters)
Y5 24 MHz Osc (FDC)
U20 57F2188 (int/KB/mouse)
U28 64F0942 (UART/parallel)
U43 N82077AA Floppy Controller
U52 22V10-25 35F3798
U57 DSKBOOT 64F3110
F1 2A Fuse
F2 3A Fuse
F3 5A Fuse

J7 pre-installed Japanese Display Adapter B-II (or XGA-2)
J12 pre-installed SCSI /A with cache adapter
J11/J12 are not for SIMM risers, they are standard 32-bit MCA slots.
J13/J23 are not card-edge power connector. They are pin type connectors to which a pair of female connectors from the PSU plugs.

Processor Complexes

60-W0x Complex (486DX 25 MHz)
60-W1x/W2x Complex (486SX 25 MHz / 486DX2 50 MHz)
N / DX2-66 Upgrade Type-B Complex (486DX2 66 MHz)

Model Types

As described HERE there are 4 types of 5560:

  • 5561-W0x - 486DX25: If you have filled all SIMM sockets with 8 MB SIMMs, you'll have enough time for cigarettes and a cup of coffee (or two) until the machine finishes the memory count.
  • 5561-W1x - 486SX25: Faster memory count than -W0x.
  • 5561-W2x - 486DX2-50: Most likely the same complex as in -W1x.
  • 5561-Nxx - 486DX2-66: Supercharged 5560 with a Type-B DX2-66 upgrade platform.


W08, W0B, W0C
W18, W1B, WYA, WYB
W28, W2B, WA8, WAB
4MB (70ns)
4MB (8MB for WAx)
1MB (PS/55 Display Adapter) B-2 ?
3.5" x1 (1.44MB/720KB)
Last digit of type code indicates HD capacity (8; 80MB, B; 160MB, C; 360MB)
Option Slots (free)
32bit full size x3, 32bit half size x1
Storage bays (free)
Dimension (mm)
440 (W) x 430 (D) x 140 (H)
Weight (Kg)
AC Input
AC100--120V 50/60Hz, 215W (MAX)
OS installed
WYx; S/2 J2.0 & DOS J5.0 WAx; S/2 J2.0 & DOS J5.0


Model 5560-N Brochure

NYB *1
16MB (70ns)
1MB (PS/55 Display Adapter) B-2 ?
3.5" x1 (2.88MB/1.44MB/720KB)
Option Slot (free) 32bit full size x3, 32bit half size x1 32bit full size x2, 32bit half size x1
Storage bays (free)
Dimension (mm)
440 (W) x 430 (D) x 140 (H)
Weight (Kg)
AC Input
AC100--125V 50/60Hz, 194W (MAX)
OS installed
OS/2 J2.0 & DOS J5.0 OS/2 J2.0 & MCADAM OS/2 J2.0 & MCADAM

*1 NYB : OS/2 model
*2 NMB : MCADAM/2 ( CAD software ) included. ASYNC TTL /Adapter is included.
*3 NMY : MCADAM/2 upgrade version. ASYNC TTL/Adapter is included.


8 x 72-pin SIMM sockets mounted directly on the planar.
Parity 8 MB/70 ns SIMMs are mandatory for -W1, -W2 and -N complex.
For W0 complex, 80 ns SIMMs are standard, and must be used in matched pair.
For W0/W1 models, reference Ver. 1.11 is required to use RAM's more than 16MB.


No video on the planar.
32-bit BVE slot with PS/55 Display Adapter B-2 installed.
32-bit AVE slot available.

SCSI Adapters

Uncached 16-bit SCSI /A was used for model -W0, but I don't know if it was the long or short version.

A stock SCSI /A for -W1/W2 models is a half length 32-bit adapter with AT-like 50-pin header. It uses the usual @8eff (32-bit with cache) ADF. SCSI microcode set is 64F4376/4377. Outline HERE.

Model 5560-N was equipped with a short SCSI Adapter II/A (32-bit) with 512 KB cache (which is IDed as 06G6760 in sales leaflets, and I think it's either 35G2818 or 07G3063.)

Inner View

Photos below are inner view of my 5561-W1B with Type-B Upgrade processor complex installed. Half-sized cached SCSI /32A with 50-pin header was replaced with a short caching SCSI /A -II/32A with new micro code set.
   You can see an AMD 5x86-133 CPU on an interposer with a low-profile heatsink. The CPU runs at 160 MHz (internal). No CPU fan, but the front fan blows a fresh air over the heatsink.

Picture #1 (click to enlarge)

Adapters (top to bottom):

J9: Madge Smart Ringnode MC32
J7: XGA2
J8: Intel Fax/Modem Adapter
J5: Processor complex DX2/66 Upgrade Type-B
J11: (empty)
J12: Short Cached SCSI with new Microcode

CPU closeup #1
CPU closeup #2

Picture #2 (click to enlarge)

View of the SIMMs and Power Connectors:

You can pull the PSU up and then swing it to right side, similar to Model 95.

Notice how different the power connections are when compared to Model 90.

Tall SIMMs are not good for 5560. There isn't much space between the SIMM slots and the PSU.

My 5561-W1x (upgraded with 60-N complex)

64 MB of RAM, BIOS modified N complex with 80 MHz OSC, AMD 5x86 running x4 speed, ATI-GUP, Madge Ringnode MC32, Genuine IBM SCSI /32A with cache, 650 MB + 1 GB hard drive, Hitachi 2x CD-ROM without bezel.

Content created and/or collected by:
Louis Ohland, Peter Wendt, William Walsh, Kevin Bowling, Jim Shorney, Tim Clarke, David Beem, Tatsuo Sunagawa, Tomáš Slavotínek, and many others.

Ardent Tool of Capitalism - MAD Edition! is maintained by Tomáš Slavotínek.
Last update: 12 Jun 2021 - Changes & Credits | Legal Info & Contact