Changes and Credits

Existing Content
New Content

Existing Content

This website features content from the original Ardent Tool by Louis Ohland. In addition, it includes material from many other PS/2 and MCA-oriented websites. Namely:

Credit for the original content goes to the respective authors listed above.

Aside from the above sources, many other pages were merged to the MAD Edition (see changelog). The name of the original author should always be noted either on the page itself or next to the link that leads to the particular page.

If you are one of the authors and you can't find your name anywhere, want to request some edits or content removal, please don't hesitate to contact me.

Most of the Email links are still pointed to the respective authors, as I think it's the right thing to do. Since it was them who collected or created the content. If you have a question specifically concerning this version of the website, please contact me directly.

Included in this version are some additional documents - such as technical references, brochures, patents, articles from various computer magazines, etc. Authors of these materials are either named explicitly on the page from where they can be accessed and/or are named directly in the material itself.

New Content

The MAD Edition also features a significant amount of new content created by me - Tomáš Slavotínek. This includes technical explanations, tutorials, various text notes, board outlines (TS signature), schematics and other illustrations, pinouts, reverse-engineering and measurement results, hardware modifications, and more.

Many of the pre-existing pages were modified, merged, cleaned up, etc. These changes include complete overhauls, improved and more consistent formatting, fixed links, and other adjustments. Some of the illustrations, tables, and other content were completely reworked. The main index page has been redesigned from a scratch and should be much easier to navigate now.


Considering the scale of the project, it would be nearly impossible and of little value to mention every single change here. However, for those interested, a list of the most important additions and modifications can be found down below.

Even some relatively large updates might be missing from here because I simply don't recall all the changes that were made during the early days. And even now I sometimes forget to update this page. Version control you say? Yeah, maybe one day...

6 Jan 2021 – 20 Jan 2021

   [1] Information extracted and patching done by Tomáš Slavotínek
   [2] Scanned by Derek Newland (original link)
   [3] Content by Louis Ohland, modified by Tomáš Slavotínek
   [4] Photos from ebay seller "elizabethole-0" (edited)
   [5] Photos from Tatsuo Sunagawa (Sandy)
   [6] Scans/photos/outlines/ROM dumps by Tomáš Slavotínek
   [7] Photo by Lorenzo Mollicone
   [8] Photos and ROM dumps by David Beem

28 Dec 2020 – 2 Jan 2021

   [1] Photo from ebay seller "pro-data" (edited)
   [2] Scans by Tomáš Slavotínek
   [3] Image presented by Dave from EEVBlog, x-rayed by CPU Galaxy
   [4] Outline created by William R. Walsh, modified by Tomáš Slavotínek

14 Dec 2020 – 24 Dec 2020

   [1] Articles HTMLized by Louis Ohland, edited by Tomáš Slavotínek.
   [2] Photos and BIOS images provided by David Beem
   [3] Scans by Tomáš Slavotínek
   [4] Photo by Louis Ohland

9 Dec 2020

  • Louis Ohland "transfers all command functions" to

25 Nov 2020 – 9 Dec 2020

   [1] Photos and BIOS images provided by David Beem
   [2] Photos from ebay seller "ctesales" (edited)
   [3] Photo from Wikimedia user "Darklanlan"
   [4] Photos from Tatsuo Sunagawa (Sandy)
   [5] Documentation provided by Tatsuo Sunagawa (Sandy), scanned by Tomáš Slavotínek.

1 Oct 2020 – 21 Oct 2020

20 Sep 2020 – 25 Sep 2020

  • Added all missing PS/55 Files. Files provided by Sandy. Thanks! Page cleanup.
  • Added Model 30 index page and Common Devices page
  • Added Model 30 and Models 35/40 planar pages. Mostly empty currently.
  • Model 25 - added hi-res planar (T1 & T2) and riser photos [1]
  • Model 30 - added hi-res planar (US & Greenock) and riser photos [1]
  • Models 35/40 - added hi-res planar and riser photos [1]
  • Model 25 SX - added hi-res planar (L & H) photos [1]
  • 486 Interposers and Upgrades - added link to Jan Steunebrink's AMD 5x86 page.
    All relevant pages now link to this Upgrade page. Thanks for the heads up, Tim.
  • Added a few more Patents. Mostly posted by Louis. Thanks!
    Reformatted the table and added links back to Google Patents.
  • Fixed a bunch of typos and other errors across the website.
  • Switched the index pages and this changelog to the DD Mmm YYYY date format.

   [1] Photos provided by David Beem. Thank You!

4 Sep 2020 – 8 Sep 2020

  • Merge of the latest Louis's changes; snapshot taken 4 Sep 2020
  • Reworked the SCSI Errors page
  • POS Operation - tweaked formatting, some minor info corrections
  • Many other minor changes across the site

1 Sep 2020

7 Aug 2020 – 27 Aug 2020

31 Jul 2020 – 2 Aug 2020

   [1] Photos provided by Wolfgang Gehl. Thank You!

7 Jul 2020 – 10 Jul 2020

16 Jun 2020 – 17 Jun 2020

11 Jun 2020 – 14 Jun 2020

15 May 2020 – 16 May 2020

9 May 2020 – 11 May 2020

5 May 2020 – 6 May 2020

1 May 2020 – 2 May 2020

17 Apr 2020 – 24 Apr 2020

14 Apr 2020

7 Apr 2020 – 9 Apr 2020

4 Apr 2020 – 5 Apr 2020

2 Apr 2020 – 3 Apr 2020

27 Mar 2020 – 28 Mar 2020

  • Merge of the latest Louis's changes; snapshot taken 26 Mar 2020
  • A minor index page update, some sub-index pages updated as well
  • IBM HD Pinouts - uses global pinout styles now
  • 9585 "X" Planar, 9585 "K"/"N" Planar - cleanup, links, datasheets, etc.
  • Some other minor changes

24 Mar 2020 – 26 Mar 2020

14 Mar 2020

22 Feb 2020

  • Updated Online INF Book Reader to version 0.3a. Added "About" page.
  • T4 "N" and "Y" - updated outlines
  • Additional info about T4 Flash ROM + programming voltages
  • T4 pages - corrected some errors + clean-up
  • Added more PS/2, MCA patents (posted by Louis)
  • Streamlined the main index and some sub-index pages for easier navigation
  • The "Complex Thoughts" page now serves as the main "Processor Complex" index. All processor complex-related pages can be reached from here now.
  • Added "MCA Pinouts"
  • Reworked the "MCA Slots" page. Replaced the original ASCII art with pictures.
  • Moved the HIMEM.SYS Update info to its own page.
  • T4 - added info about diag. LEDs
  • T4 - added info about SDL POST diags and SDL POST diag jumper
  • Op Panel - added some SDL info
  • Added SDL programming page

31 Jan 2020

  • Updated Online INF Book Reader to version 0.3
  • Added ServerGuide 3.01 INF files (thanks Tim)
  • Added IVIEW 2.1, level 100 (fixes some font rendering issues)

21 Jan 2020

  • Updated Online INF Book Reader to version 0.2

20 Jan 2020

  • Added Online INF Book Reader

2 Jan 2020 – 4 Jan 2020

  • Added Operator Panel Upgrade for 9585 K/N
  • Added ServerGuide 2.50 INF files (thanks Wolf)

26 Dec 2019 – 27 Dec 2019

  • Minor index and disks page tweaks
  • Links/media links update

1 Dec 2019 – 16 Dec 2019

  • Index page update, sections reorganized
  • Minor Operator/Indicator Panel changes, 85 Indicator Panel schematic update
  • Added Flash ROM info page
  • Reworked 85 K/N planar outline and description
  • Updated 9595, Bermuda, and Lacuna planar outlines and description
  • Merge of the latest Louis's changes; snapshot taken 15 Dec 2019

20 Nov 2019 – 23 Nov 2019

  • Index page update, new index menu, reworked sub-sections, a little bit of SEO
  • Fixed some broken links and URL case inconsistencies.

14 Nov 2019 – 16 Nov 2019

  • Updated and fixed the Processor Complex Matrix (from Louis)
  • Added Tech. Ref. for PS/2 76/77 i/s, Server 85, Server 95, 95A (INF) (from Louis)
  • Index page update (simplified and reorganized)
  • New index pages for PC, RT, RS/6000, ThinkPads, and other systems
  • Tweaked colors of the PS/2 form factor previews
  • New index image (from Wikipedia, made by Raymangold22, public domain - CC0)
  • Reorganized the Needham's Programmers section a bit
  • Added a few more IBM patents
  • Added some new POST/IML error codes + other minor tweaks

26 Sep 2019

  • Model 76/77 - added some more flash BIOS files, minor cleanup

21 Aug 2019 – 23 Aug 2019

  • Added RM Nimbus index and files
  • Added some Olivetti files
  • A few additions to the Link collection
  • Minor index update and some other changes
  • Tweaked "Peter H. Wendt's Adapter Picture Collection and made it available locally

18 Aug 2019

  • Made The MAD Edition available online at Finally!

4 Jul 2019 – 17 Aug 2019

  • Cleaned up a few pages
  • Localized a few more links, added internal links
  • Promoted the "ALR files" page to a proper ALR index page
  • Added NCR index page, NCR file libraries, system files, documents, etc.
  • Added Olivetti index page, Olivetti system list, service guides, documents, etc.
  • Configuration index and Technical Background index are now two separate pages
  • Technical Background - added info about MCA-specific programming routines
  • Imported Model 25 pages from William R. Walsh's website + new sub-index
  • Imported EduQuest pages from William R. Walsh's website + new sub-index
  • Added Apricot index page, system info, and some files.
  • Merge of the latest Louis's changes; snapshot taken 17 Jul 2019
  • 95/95A planar cleanup, new outlines, fixed links
  • Parallel port & mouse cleanup (fixed links, localized files, reworked tables, etc.)
  • Floppy pinouts reworked tables, added 40-pin planar pinout, cable diagrams...
  • Resolved the networking index vs adapters index vs main index redundancy
  • Localized Token Ring NIC benchmarking info from Wolfgang Gehl
  • Added Infotronic IGP64 CHROMA/MCA page, based on info from Wolfgang Gehl
  • Resolved the 9590 planar vs 9590 Common Devices redundancy
  • Added a proper 9590 index page, cleaned up the 9590 pages, new planar outline
  • Cleaned up the Op Panel page, replaced all the ASCII-art with proper schematics
  • Added some more PS/2 and MCA patents held by IBM, new patent folder and index
  • Added memory technology docs from IBM Microelectronics (DRAM, VRAM, etc.)
  • Reworked the Op Panel page, added schematics for 85, 95 XP, and 95A panels, pinouts and much more...
  • Localized Intel FDIV Processor Replacement Program pages
  • Localized Processor Complex-related IBM Technical Disclosure Bulletins + links
  • Reworked the PS/55 and Multistation index pages, fixed up a few other PS/55 pages.
  • Added memory chip conversion chart (DRAM, SRAM, EPROM, FLASH...)
  • Fixed a multitude of broken links and URL case inconsistencies.
  • Some final pre-release touches across the board.

29 May 2019 – 25 Jun 2019

  • Merge of the latest Louis's changes; snapshot taken 29 May 2019
  • Cleaned up a few pages
  • Localized a few more links
  • Fixed some internal links
  • Added a few more scans/articles
  • Removed some more duplicate pages (serial, parallel, error index, etc.)
  • Added a list of the RETAIN books
  • Added PS/2 brochures (from

30 Apr 2017 – 13 Jun 2017

  • Merge of the latest Louis's changes (apart from some "broken" bits, and parts that were already tweaked in the MAD Edition); snapshot taken 30 Apr 2017
  • Added PS/2 Model List and PS/2 Form Factor pages
  • Added a collection of PS/2 and MCA related articles from PCMag, InfoWorld and other mags. (Thanks Google Books!)
  • Added a few more PS/2 PDFs
  • Added local copy of reconstructed Piper Research website
  • Added Kingston Files
  • Cleaned up a few pages (burn in hell WYSIWYG HTML editors!)
  • Localized a few more links
  • Some plain text tables reworked to HTML format
  • Added 6900 - Personal Typing System page with info and pics from Scott Peterson
  • Added detailed 8580 20 MHz planar layout picture and component list
  • Reworked/corrected/added a few more planar layouts (8525, 8530...)
  • Added a list of common IBM PS/2 ASICs
  • Added Technical Information Catalog (by IBM) - list only, no files
  • Added PCI/Micro Channel White Paper (by IBM) - PCI/MCA comparison
  • Added local copy of (MCDA) Micro Channel Developers Association, just for fun...
  • Fancy new index images
  • Fixed/tweaked PS/55 and Multistation "Timelines"
  • Tweaked a few more PS/55 and Multistation pages (mostly formatting)
  • Added Kentie's Model 95 and Model 95 Case Conversion pages
  • Reorganized the Networking sections
  • Added CNet 650E/2 adapter info and files
  • Added/localized 3Com EtherLink/TokenLink files

16 Aug 2016 – 1 Sep 2016

  • Merged with many other PS/2 and MCA-oriented websites (see above)
  • Index page reworked
  • PDF documents section extended and cleaned up (added files from MCA Mafia, schematics...)
  • Some missing bits and pieces (pages, pictures...) recovered. Thanks!
  • Localized many external pages and files (pictures, documents, binaries...)
  • Many internal links fixed
  • Some duplicate pages and sections removed or merged; links updated accordingly
    (Like the four, mostly identical, versions of the "SCSI w/Cache" page.)
  • Some plain text tables reworked to HTML format
  • Some pictures reworked, tidied up, etc.
  • Fixed formating of many pages (to a truly unified form shared across the website)
  • Other minor changes (typos, text formating, file names, dir. hierarchy...)

16 Aug 2016

  • This is where and when it all started. Created an offline copy of Louis's Ardent Tool for personal use. (Why? Read the full story HERE.)

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