IBM PS/1 User Manual

Product Description
This book contains service information for all models of the IBM PS/1 Com-
puter, Machine Types 2133, 2155, and 2168, worldwide. Machine Type
2133 contains bays for three diskette/hard disk drives and slots for three
adapter cards. Machine Type 2155 contains bays for five diskette/hard disk
drives and slots for five adapter cards. Machine Type 2168 contains bays
for six diskette/hard disk drives and slots for eight adapter cards.
For ordering information for all FRU parts, see Appendix, “Model Configura-
tions and FRU Part Numbers” on page A-1.
Security
Power-on password
System boards
386SX—25MHz processor (72-pin memory SIMM)
Three system boards available (refer to “System Board Layout” on
page 5-1):
1. Soldered on board—2MB system memory and 256 kilobytes
(K) video memory (DRAM)
2. Soldered on board—2MB system memory and 512K video
memory (DRAM)
3. Soldered on board—4MB system memory and 512K video
memory (DRAM)
Each system board contains:
– Math coprocessor socket.
– Two 72-pin system memory sockets (accepts 70 to 85 ns).
Maximum Memory = 16MB. Refer to “System Memory” on
page 1-20.
– Ports include: serial, parallel, keyboard, mouse, and video.
– Connectors for AT* riser card (120-pin), input power (12-pin),
AT diskette drives (34-pin), IDE AT hard disk drives (40-pin),
power LED (2-pin), hard disk LED (2-pin), and video feature
(26-pin).
– Lithium battery.
486SX—20MHz/25MHz processor (30-pin memory SIMMs)
– Math coprocessor socket.
– Supports 8K internal cache. (External cache is not supported.)
General Information 1-5

IBM PS/1 Specifications

General

Processor	Intel 80286 or 80386
Processor Speed	10 MHz (80286)
RAM	1 MB (expandable to 2 MB or more)
Storage	40 MB hard drive
Floppy Drive	3.5" 1.44 MB
Graphics	VGA
Ports	Serial, Parallel, Mouse