Category Archives: IBM

PC Keyboard: The First Five Years

The vast majority of PC users today have no memory of what PC keyboards looked like before the standard 101/102-key layout arrived, even though various OEMs do their best to mangle the standard layout in order to minimize usability, especially … Continue reading

Posted in IBM, Keyboard, PC hardware, PC history | 19 Comments

PowerPC Archival

For the 0.7 persons out there who have a working IBM Power Series desktop but not OS/2, here’s the first and final release of OS/2 for the PowerPC, from December 1995, as well as a beta plus cross-development SDK from … Continue reading

Posted in Archiving, IBM, OS/2, PowerPC | 2 Comments

Why Does Windows Really Use Backslash as Path Separator?

More or less anyone using modern PCs has to wonder: Why does Windows use backslash as a path separator when the rest of the world uses forward slash? The clear intermediate answer is “because DOS and OS/2 used backslash”. Both … Continue reading

Posted in DEC, DOS, IBM, Microsoft, PC history | 41 Comments

ThinkPad Fan

I suppose I am one, but recently I had trouble with the other kind of a ThinkPad fan. An elderly ThinkPad 43p with a 2.13 GHz CPU (Dothan Pentium M with 2MB L2 cache) and a rather nice 1600×1200 IPS … Continue reading

Posted in Hardware Hacks, IBM, ThinkPad | 4 Comments

A Sound Card Before Its Time

A mysterious full-length sound card recently arrived at the OS/2 Museum. It was clearly manufactured by IBM in 1985, and sports a 20 MHz Texas Instrument TMS32010 DSP (the DSP is the large black DIP chip near the lower left … Continue reading

Posted in IBM, PC history, Sound | 20 Comments

How Fast Is a PS/2 Keyboard?

A few weeks ago, an interesting question cropped up: How fast is a PS/2 keyboard? That is to say, how quickly can it send scan codes (bytes) to the keyboard controller? One might also ask, does it really matter? Sure … Continue reading

Posted in Borland, IBM, Keyboard, PC hardware | 14 Comments

OS/2 2.0, Spring ’91 Edition

Thanks to a generous reader, a curiously nondescript box labeled “OS/2 32-Bit Pre-release” recently turned up at the OS/2 Museum. The box looks very much like retail IBM products from the early 1990s, but has no identifying description except for … Continue reading

Posted in IBM, Microsoft, OS/2, PC history, Pre-release | 34 Comments

The A20-Gate Fallout

A recent post explored the motivation (i.e. backwards compatibility) to implement the A20 gate in the IBM PC/AT. To recap, the problem IBM solved was the fact that 1MB address wrap-around was an inherent feature of the Intel 8086/8088 CPU, … Continue reading

Posted in IBM, Microsoft, PC architecture, PC history | 91 Comments

The A20-Gate: It Wasn’t WordStar

Although WordStar was long suspected to be the reason (or at least one of the major reasons) for implementing the A20 gate hardware on the PC/AT and all the associated problems later on, it is now all but certain that … Continue reading

Posted in 286, IBM, Microsoft, PC history, WordStar | 37 Comments

Pascal Out Of Memory

Suppose you want to run the original 1981 vintage IBM Pascal 1.0 (supplied by Microsoft) on a PC that is less than 30 years old. Upon execution, PAS1.EXE may well fail with the following error: Error: Compiler Out Of Memory … Continue reading

Posted in Bugs, Corrections, IBM, Microsoft, PC history | 40 Comments