8048x > IntelA80486SX-25-33
Modified: April 23, 2005, 4:27 pm
Speed:33MHz Max
Data Code:9435
Transistors:1.2 million
Process:1 Micron
Architecture:32 bit CISC
Used in:Computers
Description:The successor to the 80386 processor, Intel 80486
(i486) added new important features:

Floating Point Unit was integrated with the

Internal clock doubling and tripling allowed the
processor to run much faster in existing

Power management features and SMM (System
Management Mode) became a standard feature of the

Instruction set optimization resulted in even
greater performance of the processor. Different
versions of the 80486 were produced, two most
common versions are 80486DX with integrated FPU,
and 80486SX without FPU. The Intel 80486 was
produced at speeds up to 100 MHz. AMD produced
even faster 120 and 133 MHz versions of the 80486.

Early SX chips had the FPU disabled, later ones
had it removed from the die completely, saving
400,000 transistors.

DX/SX = 1x Multyplier (8k Cache)
DX2/SX2 = 2 x Multyplier (8k Cache)
DX4 = 3x Multiplier (16K Cache)

Bus Speed: 33MHz
This SX has been requalified by Intel for 33MHz
operation. This is a very late SX chip
which means Intel probably had a special contract
to fill. The FPU is disabled in this SX.