IBM Personal System/2 Model 55 SX

General information
Machine type: 8555
Announce date: May, 1989 (55 SX)
List price: $5545.00 (8555-031)

Excerpt from the original announcement letter;

The Model 55 SX enhances the Personal System/2 family of systems by offering 32-bit microprocessor compatibility at a price range previously occupied by 16-bit 80286 systems. The desktop system is highlighted by the Micro Channel(TM) Architecture with a 16 MHz 80386SX 32-bit microprocessor, high density memory technology and a wide range of integrated features. With the capability of supporting up to 16MB of high speed real memory, 30MB or 60MB of disk storage, advanced graphics and an optional 80387SX Math Co-Processor, this system provides significant performance improvements for 80286 users.

System Characteristics
Microprocessor: Intel 80386sx (32 bit)
Clock speed: 16 Mhz, 0-2 wait states
Coprocessor: socket for optional i80387 math coprocessor
Type of BUS: 16-bit MCA (Micro Channel)
Total number of expansion slots: 3
Ports: PS/2 keyboard, PS/2 mouse, serial, parallel, VGA

Min/Max on system board: 1/4MB (16MB max. using adapter cards)
Type of memory:
RAM: DRAM (PS/2 72-pin SIMM, 2 sockets) 85ns parity checked
ROM: 128kb
Cache: n/a

Physical description
Power supply: 90w, 110-220VAC
Weight: 8.65 kg (19 lbs)
Dimensions (HxWxD): (102 x 406 x 397mm)

Mass storage
Drive bays: 2 3.5" half-height
Floppy Disk
Size: 3.5 inch half-height
Capacity: 1.44MB
Hard disk
Size: 3.5 inch half-height
Capacity: 30MB / 60MB
Access time: 39ms (30MB), 27ms (60MB)
Interface: ST-506 (30MB), ESDI (60MB) PS/2 connector

Display type: Optional Analog CRT
Graphics modes supported: Integrated VGA Display adapter

320x200, 256 colours
640x480, 16 colours

Type: 101 key enhanced

Operating system: IBM PC DOS Versions 3.30 or higher

Various memory, diskette drive, hard drive, monitor, and keyboard configurations including;
8555-031 - System Unit 386-16Mhz,2MB,30MB,1.44MB
8555-061 - System Unit 386-16Mhz,2MB,60MB,1.44MB
8555-LT0 - System Unit 386-16Mhz,2MB,Token Ring (medialess workstation)
8555-LE0 - System Unit 386-16Mhz,2MB,Ethernet (medialess workstation)