Intel 486 DX

From cpudb

An Intel 486 DX Processor
Manufacturer:	Intel
Codename:	P4
Interface:	Socket 3
Instructions:	IA32 (x86)
Packaging:	CPGA
Speeds:	25MHz-50MHz
FSB:	25MHz-50MHz
Transistors:	~1.2 Million
L1 Cache:	16KB
Process:	1000nm-800nm (1.0 µ-0.8µ)
In Production:	No
Date:	1989-1993

The Intel 486 DX processor, first introduced in April 1989, picked up where the 386 left off, and brought several important features to x86 processors, such as:

• An integrated floating point unit (FPU)
• Power management features
• An optimized instruction set, providing better performance
• Several other architectural enchancements

Intel's DX model of 486 was the first version. Intel later expanded its 486 product line with several different versions of the 486, including:

• The 486 SX, a low cost version of the DX, without an FPU
• The 486 SX2, a clock-doubled SX
• The 486 SL, a low power DX intended for use in laptops
• The 486 SL-NM, a low power version of the SX, for use in budget laptops
• The 486 DX2, a clock-doubled DX
• The 486 DX4, a clock-tripled DX

DX processors did not feature clock multipliers, which are a standard feature of processors today. As a result, they were limited in how fast they could operate, since the front side bus had to operate at the same speed as the processor's internal clock. This caused stability issues when trying to make chips run at high clock speeds. The DX was made obsolete by the DX2, which introduced clock multipliers, allowing the CPU to run at twice the speed of the front side bus.