Category Archives: 386

IBM XENIX 1.0 Incompatibility Details

Some time ago I wrote about IBM PC XENIX 1.0 and why it won’t work on 386 and later processors. Thanks to a kind reader, I’ve been able to analyze the object files used to link the kernel, and I believe … Continue reading

Posted in 286, 386, Microsoft, Xenix | 18 Comments

Shiniest x86 Chip

While there have been many shiny new chips in the metaphorical sense, x86 (and x87) chips have never been known to be literally shiny. The typical packaging is ceramic or some form of brushed metal, and neither of these surfaces is … Continue reading

Posted in 386, C&T, PC hardware | 6 Comments

Getting Organized, Finally

After years of looking for a good storage solution for 386 chips, I accidentally stumbled upon it: This is a relatively modern CPU tray, designed for—I believe—Socket G processors, It turns out that old ceramic PGA 386s fit in the … Continue reading

Posted in 386, PC hardware | 10 Comments

Deskpro 386 at 30

30 years ago, in September 1986, Compaq announced the Deskpro 386, a PC as revolutionary as it was conservative. Compaq decided to forge its own path and not wait for IBM to introduce a 386-based PC. At the same time, Compaq … Continue reading

Posted in 386, Compaq, IBM, PC history, PC press | 17 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 | 16 Comments

386 LOADALL

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 | 25 Comments

More on the C&T Super386

Since last week’s post, more information about the Chips and Technologies C&T has come to light. It now appears that at least some 38605DX processors were made. Whether there is any surviving working system is still an open question (since … Continue reading

Posted in 386, C&T, Documentation | 26 Comments

The Forgotten 386

The CPUs that fit into a 386 socket are well known: Intel’s original, AMD’s exact copy, and Cyrix/TI upgrades. There is also IBM’s 386SLC which is close to a 386 but can’t be plugged into a standard 386 socket. The photo below … Continue reading

Posted in 386, C&T, PC history | 12 Comments

Fast Unaccelerated VGA?

For the purpose of comparing the relative real-world performance of various processors, it’s useful to run CPU and graphics-intensive benchmarks such as 3DBench or DOOM. To avoid benchmarking the graphics card instead, the VGA has to have enough headroom so … Continue reading

Posted in 386, ATi, S3, VGA | 17 Comments

The Nearly Ultimate 386 Board

Spurred by the acquisition of a 386 ZIF socket adapter, I revived the semi-mysterious 386 board acquired over a year ago. To recap, the board is unusual in that it has CPU frequency configurable via jumpers, but I had trouble getting anything … Continue reading

Posted in 386, Hardware Hacks, PC hardware | 7 Comments