Amiga A3640 CPU Board Repair

by James Jackson

Chapter 2
Introduction

Recently, my Amiga 4000 ceased to boot-up. Without any warning at all, it just refused to boot-up. After the initial panic wore off, I decided that I would attempt to determine the cause, and, if possible, repair it. I was successful in my endeavours to get my A4000 working, but what I discovered was so bizarre I decided I needed to share it with others.

As a preface to what I discovered wrong with my machine, let me relate a little bit of background information. First of all, no recent activity had taken place to damage the computer. For example, I had not recently inserted a printed circuit board, or memory chips, etc. I had not built up a static charge and then touched my computer, discharging thousands of volts into it. It had worked one night, and simply did not work the next. Based upon this, I suspected that there could not be too much wrong with it.

A brief description of the symptoms are in order. The computer, when turned on, would start its' power-up sequence. The hard drive would move its' heads with a short brripp-brripp. After a few seconds, the cycle would repeat. The floppy drive was not active yet, and the screen was gray. The computer was not totally dead, however, as it would respond to a Ctrl-A-A soft reset sequence, but would not get past the harddrive's brripp-brripp.

In discussing my problem with a friend, it was suggested that I look at the CPU daughterboard as the source of the problem.

Return to the Amiga Tips Menu | Table of Contents | Chapter 1 | Chapter 3
- Return to the Main Menu -

Oztronics - Copyright 1999. All rights reserved.

Oztronics
9605 Hwy 90 West, #18
San Antonio, Texas 78245 • USA
210-675-4087 • FAX 210-675-4087