8038x > IntelA80386DX-20
Modified: April 10, 2005, 7:35 pm
Manufacturer:Intel
Model:A80386DX-20
Speed:20MHz
Type:80386
Data Code:8837
Introduced:1985
Transistors:275,000
Package:132CPGA
Process:1.5 Micron
Architecture:32 bit
Used in:International Spacestation, PCs, POS Terminals
Description:The third generation of x86 family, the Intel
80386 (i386) was a complete 32-bit processor with
ability to address 4 GB of physical memory. The
processor included new protected mode, that
allowed the processor to fully utilize new 32-bit
architecture and new features, like memory
protection, paging, etc. Another new mode -
virtual mode - could be used to run old 8086
applications without switching the processor back
from protected mode to real mode. There were a
few variations of the Intel 80386:

80386DX has 32-bit external data and address
busses.

Low cost 80386SX had 16 bit external data bus and
24-bit external address bus. This processor
supported only 16 MB of physical memory.

Low-power 80386SL with power management features,
with 16-bit external data bus and 24-bit external
address bus.

Embedded 80376 and 80386EX processors.

The Intel 80386 was produced at speeds up to 33
MHz, AMD produced even faster 40 MHz version.

IBM, CHIPS, AMD, Cyrix, MC, and TI all made their
own versions of the 386.

This version has the bug fixed that originally
kept 32-bit mode from working right.
It is known as a Double Sigma version.