Category Archives: IBM

Retro-Porting to OS/2 1.0

Posted on July 20, 2023 by Michal Necasek

A few weeks ago I embarked on a somewhat crazy side project: Make the Open Watcom debugger work on OS/2 1.0. This project was not entirely successful, but I learned a couple of things along the way. The Open Watcom … Continue reading →

Posted in Development, IBM, Microsoft, OS/2, Watcom | 10 Comments

First ROM Shadowing

Posted on April 21, 2023 by Michal Necasek

The other day I was asked an interesting question: What was the first BIOS with support for ROM shadowing? In the 1990s, ROM shadowing was common, at first as a pure performance enhancement and later as a functional requirement; newer … Continue reading →

Posted in C&T, Compaq, IBM, PC architecture, PC history | 55 Comments

Learn Something Old Every Day, Part VII: 8087 Intricacies

Posted on January 23, 2023 by Michal Necasek

The other day I investigated a report that a C runtime library modification causes programs to hang on a classic IBM 5150 PC with no math coprocessor. The runtime originally contained two separate routines, one to detect the presence of … Continue reading →

Posted in 8086/8088, Development, IBM, Intel, PC history, x87 | 10 Comments

PC Disk Sector Sizes and Booting

Posted on October 26, 2022 by Michal Necasek

Everyone knows that the IBM PC established 512-byte sectors on floppies and hard disks as the standard, which survived for several decades until the advent of “native” 4K-sector drives. Of course what “everyone knows” is not necessarily the whole story. … Continue reading →

Posted in BIOS, DOS, IBM, PC history, Storage | 15 Comments

IBM AIX for IA64 (Itanium) aka Project Monterey Runs Again!

Posted on October 3, 2022 by tenox

(This is a guest post by Antoni Sawicki aka Tenox) Project Monterey was an attempt to unify the fragmented Unix market of the 90s in to a single, cross vendor Unix OS that would run on the upcoming Intel Itanium … Continue reading →

Posted in IBM, Intel, SCO, UNIX | Tagged , , , , , , , | 10 Comments

Slovenian OS/2 Warp 4

Posted on September 11, 2022 by Michal Necasek

This is a guest post written by Marko Štamcar from the Slovenian Computer Museum in Ljubljana. Additional context and commentary from the OS/2 Museum can be found at the end of the article. Slovenia being a tiny country with a … Continue reading →

Posted in IBM, OS/2, PC history | 14 Comments

Learn Something Old Every Day, Part V: Early IBM PS/2 Hard Disks

Posted on May 1, 2022 by Michal Necasek

So I have been (again) trying to properly archive old MS OS/2 SDKs. The version 1.02 SDK from December 1987 (corresponding to OS/2 1.0) turned out to be a bit of a poser. The SDK came on both 3.5″ and … Continue reading →

Posted in ESDI, IBM, PC history, PS/2 | 16 Comments

OS/2 6.304: Finally Complete

Posted on April 29, 2022 by Michal Necasek

Some time ago, I lamented that even though the OS/2 Museum had a good number of disks of the final OS/2 2.0 beta, level 6.304, there wasn’t enough to install the OS, let alone any of the development tools or … Continue reading →

Posted in CD-ROM, IBM, OS/2, PC history, Pre-release | 5 Comments

Page Too Big

Posted on April 22, 2022 by Michal Necasek

The other day I was able to look at an IBM OS/2 pre-release CD-ROM from early 1992. The CD-ROM appears to have been produced by IBM UK under the DAP (Developer Assistance Program) umbrella. The CD-ROM contains about 250 MB … Continue reading →

Posted in Documentation, IBM, OS/2, PC history | 4 Comments

Vague Standards are Trouble

Posted on April 7, 2022 by Michal Necasek

Through the course of time I’ve been going over the IDENTIFY data of various old IDE hard disks. Today I happened to come across a Conner CP30254H drive, apparently made in June 1993 or so. This is a circa 250 … Continue reading →

Posted in Conner, IBM, IDE, PC history | 4 Comments