Retro Computing Archives

Aztech sound cards: Underrated OPL3

Dave Farquhar Retro Computing August 25, 2021October 14, 2021

Sometimes when you go through a pile of old parts, you find a diamond in the rough. An Aztech sound card is a great example. They sound like they ought to be standard fare ’90s junk, with poor compatibility and poor sound quality. But it turns out they have a genuine Yamaha OPL3 chip in them. They may be the cheapest way to get a real OPL3 left.

Dave Farquhar

David Farquhar is a computer security professional, entrepreneur, and author. He has written professionally about computers since 1991, so he was writing about retro computers when they were still new. He has been working in IT professionally since 1994 and has specialized in vulnerability management since 2013. He holds Security+ and CISSP certifications. Today he blogs five times a week, mostly about retro computers and retro gaming covering the time period from 1975 to 2000.

dfarq.homeip.net

286 vs 386SX

Dave Farquhar Retro Computing August 18, 2021March 2, 2026

The Intel 386 SX CPU quickly replaced the 286 CPU in the early 1990s. For a time, it was a very popular CPU, especially for people who were wanting to run Microsoft Windows 3.0 or 3.1. Yet the two CPUs run at nearly identical speed. So what was the big deal? The 286 vs 386SX argument could be confusing in 1991, and it’s not much clearer today.
Read more

Dave Farquhar

dfarq.homeip.net

Apple Macintosh vs Lisa

Dave Farquhar Retro Computing August 12, 2021April 27, 2026

A coworker asked me what the difference was between the Apple Macintosh and the Lisa. Admittedly, it’s hard to compare and contrast the two. But the Lisa was more than just an expensive Macintosh. Let’s take a look at the Apple Macintosh vs Lisa.

Dave Farquhar

dfarq.homeip.net

DOS boot menu explained

Dave Farquhar DOS, Retro Computing August 4, 2021September 14, 2023

MS-DOS 6 introduced a boot menu capability, a capability PC DOS inherited. This capability had the potential to eliminate custom boot floppies, but not a lot of people used it in my experience. I have them set up on my retro PCs to good effect. So here’s the DOS boot menu explained, with useful examples.

Dave Farquhar

dfarq.homeip.net

Commodore 64 replacement rubber feet

Dave Farquhar Retro Computing July 28, 2021July 4, 2021

It happens on all old computers, and even some not-so-old computers. The rubber pads that sit on the bottom of Commodore 64s to protect the desk surface and keep it from sliding around can fall off, liquify, or otherwise go missing. But even though the last ever C-64 was built sometime in early 1994, you can still get Commodore 64 replacement rubber feet. Here’s how.

Dave Farquhar

dfarq.homeip.net

Refurbish a vintage ball mouse

Dave Farquhar Retro Computing July 26, 2021February 23, 2024

I wanted a mouse for my IBM 5170 and my 386DX-33 systems, but both of them need a serial mouse. I mean old school RS-232 serial, not USB. Finding a serial optical mouse isn’t easy. Plus I wanted something that would look the part. I got an early 90s Microsoft mouse that matches the end of the 286/386 era, and a Logitech C7, but both worked badly. So I had to learn again how to refurbish a vintage ball mouse.

Dave Farquhar

dfarq.homeip.net

What was MR BIOS?

Dave Farquhar Retro Computing July 5, 2021September 20, 2023

In the summer of 2021, Youtuber Adrian Black was restoring an IBM 5170. And he lamented that he wasn’t able to get all of the original parts working together and have a machine that would do what he wanted. It wasn’t a pure IBM 5170 anymore. One of the things he did was put a Quadtel BIOS in it, which received mixed reactions. But that brought to mind another option someone who needed to soup up a 5170 in the late 80s could have used: MR BIOS. What was MR BIOS?

Dave Farquhar

dfarq.homeip.net

How to use command line FTP

Dave Farquhar Retro Computing June 30, 2021October 22, 2022

FTP is a useful way to get files to your retro PCs once you put them on your network. You can use a GUI FTP client, but command line FTP isn’t hard and doesn’t require you to install anything additional. Here’s how to use command line FTP.

Dave Farquhar

dfarq.homeip.net

Apple IIc power supply pinout

Dave Farquhar Retro Computing June 22, 2021March 24, 2023

I recently needed a new power supply for an Apple IIc to replace a missing one. It’s easy to adapt a modern laptop power brick to work with an Apple IIc. All you need is a pinout. Here’s an Apple IIc power supply pinout.

Dave Farquhar

dfarq.homeip.net

MOS 74LS logic chips

Dave Farquhar Retro Computing May 12, 2021August 19, 2026

Commodore (in)famously owned its own chip manufacturer, MOS Technology, later known as Commodore Semiconductor Group. MOS was pivotal to helping Commodore keep prices low in the early 1980s, as it lowered Commodore’s overhead, and ensured a steady supply of chips. In 1983 and 1984, MOS produced 74LS logic chips. These chips are very failure prone. Here’s how to find MOS 74LS logic chips, and more importantly, what to replace them with.

Dave Farquhar

dfarq.homeip.net