Author Archives: Michal Necasek

Seagate ST-225: Just Wow

A few weeks ago a Seagate ST-225 drive more or less accidentally landed at the OS/2 Museum. The drive is nearly 30 years old (manufactured in late 1986) and rather interestingly, this particular unit comes with a label declaring it … Continue reading

Posted in PC hardware, Storage | 35 Comments

Periscope Manuals

Some time ago I recovered a latter-day Periscope manual from storage. Since some readers might find it useful, I decided to scan the manual and convert it to PDF. It covers the basic Periscope debugger, variants and add-ons (remote Periscope, … Continue reading

Posted in Debugging, Documentation | 7 Comments

Fixing an LAPC-I

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

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?

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…

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

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

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

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

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