• Home
  • Our Books
  • Our Film
  • Games
  • About Us
  • Contact Us
  • Login

Perspectives on all eras of videogames, computers, technology, and pop culture since 2003

Login

Login
Armchair ArcadeArmchair Arcade
Armchair ArcadeArmchair Arcade
  • Home
  • Our Books
  • Our Film
  • Games
  • About Us
  • Contact Us
  • Login

Weighing in on known defect rates for the Commodore 64

Weighing in on known defect rates for the Commodore 64
Weighing in on known defect rates for the Commodore 64

Weighing in on known defect rates for the Commodore 64

February 16, 2018 Posted by Bill Loguidice Editorial, History No Comments

Inspired by a discussion on AtariAge, I was curious if there were any defect rate numbers available for the Commodore 64 to see if it indeed was significantly more failure prone than select contemporaries like the Apple II and Atari 8-bit, and how the percentages worked out (not that we’d likely ever get numbers for any of those other systems). As such, I asked the question on a big Commodore 64/128 Facebook group.

As expected, no one has been able to produce any hard numbers (again, likely a difficult, if not impossible, proposition for the vast majority of these companies; as a point of comparison, when we were writing the CoCo book, there weren’t even good sales numbers available). Besides the usual anecdotes about having issue x, y, or z, and never having any issues, etc., Bil Herd, legendary Commodore engineer, was able to provide some color commentary on the topic:

“Production did whatever they had to do to hit the numbers. They didn’t necessarily talk about it and we were not allowed on the production floor when I first got there. 

 This changed over time, I would like to think I was part of it, as I got to know the head of production (at the local bar no less) and I was adamant that we could lower the failure rates if they let us see what was going on. In one case I recommended protection diodes on the test jig as I think they were blowing out the chip on one of the ports (not even immediately, static discharge can break something later).”

In regards to the common practice of filling the power supplies with epoxy: “That was one thing we were not able to change until the 128 as the supply was procured by Commodore Japan and blessed at the highest levels.”

“C64 reliability was all about the VIC chip and a couple of other custom chips. In the early days even the best ones sparkled (so we changed the Kernal so the unused character cells on the blue screen had the foreground and background characters set to the same color, they still sparkled but it was the same color as the background).

I got there just as they were going to a Beryllium lead frame to help pump the heat out of the die.”

In regards to a comment about making a product purposefully short-lived: “Yes we never would have tried to make something fail or not last as long (as affordable) People get upset when they hear that I would not have added cost to a product if already was projected to last 3-5 years. Quite simply I would not have stayed one of the lead consumer designers if I put extra (unnecessary) cost, especially at the sales numbers of millions. (Think of 5 million dimes).”

In regards to a comment about the “nasty” power supply being the source of most of the reliability problems, randomly cooking parts as they failed, etc.: “The VIC I actually melted the case.”

“Failures take many forms also, for example there were many units that started off violating the DRAM timings and then it got worse with heat. The DRAM contents could get corrupted which may do things like result in a reboot 20 minutes later. Back then if a home computer occasionally reset it wasn’t considered to be all that unusual.”

“The C64 suffered from high ‘infant mortality’, once it got a couple of months old it would probably function like any other piece of technology for the day.”

On the idea that the biggest problem someone saw was blown out SIDs (but who lived in an area with a lot of static electricity in the winter): “The C64 SID design actually violates one of my design rules that I use. My opinion is that whenever there is a large capacitor attached to a chip it should be current limited and possibly diode protected. 

The issue is that when power is removed from SID that there is a residual voltage on the cap and now it has more voltage on that pin than the other pins including VCC.
 
The instantaneous current flow could be quite high and also violates the pin spec of the chip and forward biases stuff, etc.”

And as a follow-on to that last comment and the idea of wouldn’t it be something as simple as a drain resistor to sort that: “Usually a resistor in series, it usually can be so small so as not to add an RC pole in the case of a filter (like SID). I told the guy that tried to redesign the SID (for HMOS and other things) that he should heavily JFET/Diode protect that pin but I rather doubt he did. I don’t think he ever really listened to a SID playing either.”

Related

Tags: c-128c-64c128c64commodoreCommodore 64sx-64sx64
No Comments
Share

About Bill Loguidice

Bill Loguidice is a Founder and Managing Director for Armchair Arcade, as well as a critically acclaimed technology author and journalist.  He is also the co-founder of creative services firm, Armchair Creative Services, and a noted videogame and computer historian and subject matter expert. See full bio

You also might be interested in

New updates for the massive private vintage and modern videogame and computer auction set for May 31, 2018 in Edison, NJ!
New updates for the massive private vintage and modern videogame and computer auction set for May 31, 2018 in Edison, NJ!

New updates for the massive private vintage and modern videogame and computer auction set for May 31, 2018 in Edison, NJ!

May 4, 2018

(UPDATE 1: Check out this cool Kotaku article on the[...]

Master List of Commodore 128 Games and Software
Master List of Commodore 128 Games and Software

Master List of Commodore 128 Games and Software

Apr 2, 2018

Unable to find a single source listing of Commodore 128[...]

The original Commodore Vic-20 Prototype. [Photo credit: John Feagan]
The original Commodore Vic-20 Prototype. [Photo credit: John Feagan]

The Real Commodore Vic-20 Prototype

Oct 29, 2014

Thanks to Marty Goldberg and his post on the Facebook[...]

Leave a CommentCancel reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Recent Posts

  • How has gaming evolved across the last decade and what is next?
  • Polymega Collections Volumes 9 and 10 now available – Strikers 1945, Bases Loaded, and more!
  • How The Legacy Of League Of Legends Paved The Way For eSports Betting
  • Tech Meets Design: What Is a Flexible Monitor and Why Gamers Should Care
  • Application of Strategic Thinking in Nomini Casino Games
  • DXRACER Partners with CS2 MESA Nomadic Masters Spring 2025 to Elevate Esports Comfort and Performance
  • Playing the Long Game: A Simple Guide to Casino Money Sense
  • Best Games to Bet on This Season
  • Retro Gamers, Modern Thrills: Why Instant Withdrawal Casinos Resonate with Arcade Fans
  • Pixels and Progress: How Retro Gaming Continues to Shape Modern Technology

Recent Comments

  • Aiodensghost on Official Game List for My Arcade Atari Gamestation Pro
  • keyboredom on Quick guide on how to play on the Internet Arcade
  • Bill Loguidice on Official Game List for My Arcade Atari Gamestation Pro
  • Melanie Levenstein on Official Game List for My Arcade Atari Gamestation Pro
  • George on How to Predict CS:GO/CS2 Skins Prices?
  • Bill Loguidice on Retro Games Ltd to release The Spectrum, fully working ZX Spectrum, and here’s the game list!
  • Derek on Retro Games Ltd to release The Spectrum, fully working ZX Spectrum, and here’s the game list!
  • Bill Loguidice on Retro Games Ltd to release The Spectrum, fully working ZX Spectrum, and here’s the game list!
  • Simon on Retro Games Ltd to release The Spectrum, fully working ZX Spectrum, and here’s the game list!
  • Viktor Špička on Retro Games Ltd to release The Spectrum, fully working ZX Spectrum, and here’s the game list!

Archives

Categories

Explore

android (46) apple (37) ar (37) Arcade (165) Atari (73) atgames (173) book (99) books (98) casino (496) esports (46) firmware (43) Flashback (45) gambling (520) Gaming (40) home arcade (114) htc vive (42) humble bundle (282) humble store (67) ios (37) led (35) legends (40) legends arcade family (46) legends gamer (33) legends pinball (39) legends ultimate (71) Microsoft (40) Nintendo (70) pc gamer (65) pc gaming (52) pinball (43) playstation (55) PS4 (36) retro (34) Sega (38) slots (82) sony (51) steam (145) switch (33) technology (35) update (42) virtual pinball (36) virtual reality (116) vive (34) viveport (42) vr (121)

Affiliates

+ Amazon

The everything store

+ Humble Bundle

Game deals, including name your price bundles

+ Playasia (Play-Asia.com)

Import games and collectibles

+ DJI Store

Amazing drones and related technology

+ Razer

Amazing PC gamer products!

fullSTEAMahead365 Your total news and information resource for all things Science, Technology, Engineering / Mathematics, Art, and Medicine / Health.

Human Advancement Never Stops.

Key Site Statistics

Posts published: 2,533
Latest publish date: May 6, 2025 @ 3:42 pm
Registered user count: 99,026

Contact Us

If you have a question, would like to provide feedback, or otherwise wish to get in touch with us, use this form.

Send Message

Blog Posts by Date

February 2018
M T W T F S S
 1234
567891011
12131415161718
19202122232425
262728  
« Jan   Mar »

Social Media and RSS

Support Armchair Arcade

All editorial content © 2003 - 2025 Armchair Arcade, Inc., an Armchair Creative Services, LLC, property. All rights reserved unless otherwise indicated. All trademarks and copyrights are retained by their respective owners. No content is to be removed or reused from the Armchair Arcade Website for commercial purposes without explicit permission from the principal Armchair Arcade staff, or the original trademark or copyright holders. Armchair Arcade, Inc., is not responsible for the content of any external sources or links. Further, endorsement of any external sources or links is neither implied nor suggested.

We thank you for your support and encourage you to contact us for any reason, including, but not limited to, questions, concerns, business endeavors, or praise. Especially praise.

Armchair Creative Services, LLC, may earn compensation for sales from links on posts through affiliate and other programs. Editorial rigor and objectivity standards are strictly adhered to and any compensation has no effect on coverage or opinions.

Prev Next