IBM PS/2

Wonder MCA Part 1 – the origin

vincent / March 30, 2026 / IBM PS/2

Introduction

After hesitating for months, I finally decided to start the WonderMCA project… It is just the beginning of a very long journey to bring MCA Bus based IBM Computer a software defined card like the famous #PICOMEM or the #PICOGUS.

This project has been in my head for many years, and I have postponed it way for too long.

I will be posting here my progress as I expect this journey to be more than a walk in the park…

The story behind this project is pretty simple, it is all about frustration not being able to find MCA extension card available at a decent price. The lack of ongoing project was also a trigger.

What made me hesitate for so long was mainly:

Scarce / or very little documentation,
Almost no open project,
Lack of required skills,
Complexity of the MCA Beast

Over the last 2 years, … Read the rest

Resurrecting an IBM 8540 PSU

I finally was able to find an IBM PS/2 8540SX in a good esthetic shape with no plastic issue and all the very specific IBM screw on the back. The 8540 was one of the last (with the 8535) to be equipped with ISA bus and not the proprietary Micro Channel bus MCA. The is why, it is been highly chased by retro hunter.

In this case, this IBM was sold as not working and as it arrived the initial testing was not showing any sign of life.

The demand on this kind of computer is extremely high and almost with no offer at all, so when you see one appearing on the market one does not hesitate too long. The seller, was king enough to make the packaging strong to avoid any damages, especially on the plastic corners.

I was betting on the non starting root cause to be … Read the rest