Retro Computing Archives

486SX vs 486DX: A closer look

Dave Farquhar Retro Computing April 3, 2024April 10, 2025

When Intel released the 486 CPU in 1989, there was no SX or DX designation on it. But similarly to what they had done with the 386, they followed up with an economy version. And they borrowed the same name designations they’d used on the 386. But the difference between the economy version and the premium version wasn’t the same in the two chip generations. In this blog post, we will explore the 486SX vs 486DX.

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.

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Why the Imagination Machine failed

Dave Farquhar Retro Computing March 27, 2024June 16, 2026

Ed Smith, the designer of the Imagination Machine, says it failed because Apple released its floppy drive in 1979 and that made the Imagination Machine obsolete. I think Smith is selling himself short a bit, or perhaps he’s giving people the answer he knows everyone wants to hear. In this blog post, we’ll explore what went wrong with the APF Imagination Machine.

Dave Farquhar

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Store controllers and cables safely without damaging them

Dave Farquhar Retro Computing March 20, 2024March 16, 2024

It’s something I think we’ve all done before. You get done playing video games and you don’t want to just leave the controllers plugged into the console and laying around somewhere. So you pick up the controller, unplug it, wrap the cable around the controller, then set it aside or even put it in a box. Maybe you even disconnect the console and wrap the video cable around the console. But did you know that doing that can damage the plastics? In this blog post, I’ll show you a better way to store game controllers and consoles neatly without the risk of damage.

Dave Farquhar

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PC mouse connector types

Dave Farquhar Retro Computing March 19, 2024March 19, 2024

The last several vintage computer mice I’ve bought on Ebay were not properly described. So I figured I would write this guide because it will help people find the right mouse for a computer, and if you are trying to sell one on Ebay, properly describing the mouse connector type will help you sell it more quickly, and potentially get more money.

Dave Farquhar

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Hash collisions in computer security

Dave Farquhar Retro Computing, security March 18, 2024March 26, 2024

Last week, Robin of the YouTube channel 8-bit Show and Tell wondered out loud on Twitter why Chrome flags Netracer 1.1, a modern indie Commodore 64 game, as malware. I think this is a classic case of hashing algorithms having gone wrong. In this blog post, I’ll explain what a hash collision is, using this collision of my hobby of retro computing and my day job of information security as an example.

Dave Farquhar

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80s computer brands

Dave Farquhar Retro Computing March 13, 2024June 1, 2026

A small number of 80s computer brands are the same as today, but a lot more companies played in the field than now. Profit margins were higher then, so industry consolidation wasn’t the matter of survival that it is now. You might be surprised to see all of the most popular computer brands of today were around in the 80s. But many popular 1980s computers no longer exist in any form.

There’s a human element to 80s computing that the 90s erased. In this list, besides the familiar stories, you’ll find a computer designed by an engineer who grew up in public housing, computers designed by two women, and a company that didn’t survive its CEO dying in a car crash celebrating its IPO. While some survived the 80s and into the 90s or even today, others only lasted a few years. The 1980s were a make or break time, and many broke.

Dave Farquhar

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APF Imagination Machine

Dave Farquhar Retro Computing March 6, 2024September 25, 2024

The APF Imagination Machine was a hybrid game console/home computer from 1979 that sought to exploit a gap in the market. Although it was not a commercial success, it is a historically interesting machine and they were not the last console to attempt that approach.

Dave Farquhar

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Use an IBM 5170 without a battery

Dave Farquhar Retro Computing February 27, 2024February 28, 2024

I got tired of my IBM 5170 PC/AT draining batteries every few months. And unlike newer PCs, operating an IBM 5170 without a battery isn’t just a matter of taking the battery out, leaving it out, and relying on the BIOS to auto configure with sensible defaults. The BIOS in the 5170 wasn’t that advanced. But if you are willing to compromise on one thing, you can use a 5170 without a battery while retaining the IBM BIOS and ROM Basic so it still feels like using an IBM.

Dave Farquhar

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Why we like retro

Dave Farquhar Retro Computing February 21, 2024July 21, 2025

Why do we like retro? The question comes up from time to time on forums and podcasts and discussion groups. I think there is more than one answer, but none of them are terribly complicated. In this blog post, I’ll explore retro’s appeal.

Dave Farquhar

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SvarDOS: FreeDOS for XT-class systems

Dave Farquhar Retro Computing February 20, 2024February 19, 2024

YouTuber Tech Tangents recorded a video about the difficulty he encountered installing FreeDOS on an IBM 5150. A similar problem will exist on any XT class system. He ended up essentially having to make his own distribution to get around the limitations. I’m sure he wishes he’d known about a FreeDOS derivative that already existed to solve his problem. That derivative is called SvarDOS.

Dave Farquhar

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