Author Archives: Michal Necasek

Fixing an LAPC-I

Posted on February 27, 2016 by Michal Necasek

A few days ago my almost new (i.e. not quite 25 years old) Roland LAPC-I arrived. It’s essentially a MT-32 synth on a stick. I plugged it into a Pentium board, tried playing some music and… nothing. Was it perhaps not jumpered … Continue reading →

Posted in PC hardware, Roland | 12 Comments

Playing Football

Posted on February 19, 2016 by Michal Necasek

The Super Bowl is long over and it’s time to look at different kind of football. In Winter 1986/1987, Microsoft initiated a small skunkworks project called “Football”. The objective was to take “Sizzle”, a development branch of proto-OS/2 that would eventually … Continue reading →

Posted in 386, IBM, Microsoft, OS/2, PC history | 21 Comments

ThinkPad PC Card Boot?

Posted on February 17, 2016 by Michal Necasek

I have several 1990s ThinkPad laptops which all have PCMCIA slots. Some have a built-in CD-ROM and no floppy drive, and no support for CD booting. It would be rather useful to boot them from PCMCIA ATA cards, and the BIOS … Continue reading →

Posted in PCMCIA, ThinkPad | 23 Comments

So This Actually Works…

Posted on February 12, 2016 by Michal Necasek

In a discussion on a previous post, Richard Wells suggested that an ATI VGA Wonder-16, a 16-bit ISA VGA card, should be able to operate in an 8-bit slot. I can confirm that yes, it does: Note that the card … Continue reading →

Posted in ATi, PC hardware | 22 Comments

Basement Finds

Posted on February 12, 2016 by Michal Necasek

The other day I attacked an old and long forgotten 286 PC stashed away in the basement. The PC is dead because the power supply blew years ago and the motherboard has a non-standard power connector. But the case was … Continue reading →

Posted in 286, ATi, PC hardware | 10 Comments

Before OS/2 Was OS/2

Posted on February 5, 2016 by Michal Necasek

After almost 30 years, several disks with ancient builds of OS/2 surfaced. In this context, “ancient” means older than the May 1987 release of the first MS OS/2 SDK. In fact these disks are so old that the one thing … Continue reading →

Posted in IBM, Microsoft, OS/2, PC history, Undocumented | 55 Comments

More CPUs in NT 3.x Workstation

Posted on January 22, 2016 by Michal Necasek

The default processor limits of Windows NT 3.x are surprisingly difficult to establish. Quite possibly because although SMP was a big selling point of NT, in reality only a tiny fraction of PCs in the mid-1990s supported SMP, and of those, … Continue reading →

Posted in NT, Software Hacks | 3 Comments

Windows NT 3.1 (and OS/2) Memory Detection

Posted on January 15, 2016 by Michal Necasek

It is common knowledge that Windows NT 3.1 only recognizes up to 64 MB RAM, unlike NT 3.5 and later versions. This statement can be found in various places, including this blog. The limitation was empirically determined by installing NT … Continue reading →

Posted in BIOS, NT | 39 Comments

NT 3.1 SMP

Posted on January 12, 2016 by Michal Necasek

Generic x86 multiprocessing, Summer 1994 edition. There’s not much to say: Yep, that’s NT 3.1 running in a VM, and it sees two processors. Remember, you saw it here first!

Posted in Intel, NT, SMP | 68 Comments

386 LOADALL

Posted on January 7, 2016 by Michal Necasek

I recently came across hints suggesting that in the 1987 timeframe, Microsoft contemplated the use of the 386 LOADALL instruction in OS/2. As far as I know, no released version of OS/2 (including the SDK betas) utilized the 386 LOADALL. … Continue reading →

Posted in 386, Undocumented | 31 Comments