Alphapc64 Introduction; The Alphapc64 Motherboard; System Components And Features; Memory Subsystem - Digital Equipment AlphaPC64 User Manual

This chapter provides an overview of the AlphaPC64, its components, features,
and uses.

1.1 The AlphaPC64 Motherboard

The AlphaPC64 Motherboard (AlphaPC64) is a module for computing systems,
based on the Alpha 21064A microprocessor and the DECchip 21072 chipset.
The AlphaPC64 runs the Windows NT operating system. For information
on Digital UNIX or OpenVMS operating system support, contact your local
distributor or your Digital sales representative.

1.2 System Components and Features

The AlphaPC64 is implemented in industry-standard parts and uses a 21064A
microprocessor (CPU) running at 200 MHz to 275 MHz. The functional
components are shown in Figure 1–1 and are introduced in the following
subsections.

1.2.1 Memory Subsystem

The AlphaPC64 memory subsystem supports DRAM memory arrays of 16MB
to 512MB with a 128-bit data bus. The memory is contained in two banks of
four commodity single inline memory modules (SIMMs). Each SIMM is 36 bits
wide, with 32 data bits, 1 parity bit, and 3 unused bits with 70-ns or less
access. Figure 1–2 shows the maximum and minimum SIMM bank layouts.
The following SIMM sizes are supported:
1M x 36

AlphaPC64 Introduction

2M x 36 4M x 36 8M x 36 16M x 36
AlphaPC64 Introduction 1–1
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