Category Archives: C&T

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

Shiniest x86 Chip

Posted on January 16, 2017 by Michal Necasek

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 | 11 Comments

More on the C&T Super386

Posted on November 20, 2015 by Michal Necasek

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 | 32 Comments

The Forgotten 386

Posted on November 13, 2015 by Michal Necasek

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 | 25 Comments