IBM 770 System Board Devices and Features, lists the, system, describes, devices, System Overview

System Board Devices and Features

Figure 1-2	lists the	system	board devices and their features. The
IBM Personal System/2 Hardware Interface Technical Reference
describes	devices	common to	PS/2 products by type number.
Device	Type	Features
Microprocessor	–	Intel Pentium processor with the MMX
		technology

Ÿ 200 or 233 MHz

Ÿ32 KB on-chip cache

External

cache

–

512

KB

(write

back)

System

timers

1

Channel

0: system

timer

Channel

1: refresh

generation

Channel

2: tone generator for speaker

ROM

subsystem

–

128

KB

by

4

banks

(1

KB

equals 1024 bytes)

RAM

subsystem

–

32

to

256

MB

(1

MB

equals

1,048,576 bytes)

CMOS

RAM

–

128 bytes CMOS RAM with real-time

subsystem

clock/calendar+

4

K

byte

NVRAM

EEPROM

–

1

K bits

subsystem

Video

subsystem

–

XGA

video

functions:

ŸUp to 65,536 colors on the TFT XGA (1024x768) LCD

ŸUp to 16,777,216 colors on an external monitor

See “Video Subsystem” on page 3-2 for more details on the video subsystem.

DMA controller	1	Seven	DMA	channels	(AT compatible:)
		Four	8-bit	channels	and three 16-bit channels

Figure 1-2 (Part 1 of 2). System Board Devices and Features

System Overview 1-3