IBM PS2 Models 95XP486 90XP486 Fundamentals
Personal System/2 Models 95 XP 486, 90 XP 486, 55 LS and P75 486 Fundamentals is an IBM International Technical Support Center Redbook, document number GG24-3616-00, Release 1.0, First Edition (October 1990). It applies to the PS/2 systems and options announced in the fourth quarter of 1990: the Model 90 XP 486, Model 95 XP 486, Model 55 SX LS and Model P75 486. The abstract gives 176 pages; the PDF has 200. It was written as reference material for IBM customers and systems engineers, not as a service manual.
Contents
Page numbers are the book's own.
| Part | Chapters | Page |
|---|---|---|
| Introduction | 1.0 Introduction; 2.0 Product positioning (90/95 XP 486 p. 3, 55 LS p. 4, P75 486 p. 4) | 1 |
| Models 90 XP 486 and 95 XP 486 | 3.0 General system description; 4.0 System details and planar functions (physical specifications, operating system support, Micro Channel slot layout 4.4, battery and CMOS RAM 4.5, keyboard and mouse ports, security and SCSI security 4.7, power supply 4.8, LED display, serial and parallel ports, DMA); 5.0 Processor adapter and 256 KB cache option; 6.0 Memory subsystem; 7.0 Initial microcode load, POST and the system partition; 8.0 DASD; 9.0 XGA subsystems | 5 |
| Model 55 LS | 10.0 Hardware (power supply, memory, riser card, token-ring and Ethernet adapters, security, DASD); 11.0 Installation, including remote IPL | 99 |
| Model P75 486 | 12.0 System overview, models, physical specifications, block diagram, memory, Micro Channel and SCSI, plasma display subsystem, display capability, expansion, power supply, keyboard | 117 |
| Appendices | A Micro Channel (137); B Antialiased fonts (141); C Programming the XGA (149); D IML error codes (157); E Announcement summary, October/November 1990 (159); F Remote IPL reference (163) | 137 |
Figures a repairer can use
- Battery (4.5): the 90 XP 486 and 95 XP 486 use a flat 3 V coin cell for the real-time clock (64 bytes of non-volatile RAM, holding setup data such as the password) and a separate 8 KB CMOS RAM that holds the configuration. IBM gave a life expectancy of 7 to 10 years depending on use.
- Power supplies (4.8): the 8590 has a 194 W auto-sensing supply (90-137 V or 180-265 V AC) and an electrical push-on, push-off power switch at the front; the 8595 has a 329 W supply whose input range must be set by switch.
- P75 486 (12.11, 12.13): auto-sensing supply for 100-240 V at 50/60 Hz; the keyboard is the same as the P70's.
- IML error codes (Appendix D) for the machines that load their POST and BIOS from the system partition.
What this document does not contain
It has no FRU numbers, removal procedures, Symptom-to-FRU index, schematics or component values. For register-level detail it refers to the model technical references and the Hardware Interface Technical Reference.
Download: IBM PS2 Models 95XP486 90XP486 Fundamentals.pdf