1970s Processors

	4004	8008	8080	8086	8088
Introduced	11/15/71	4/1/72	4/1/74	6/8/78	6/1/79
Clock Speeds	108KHz	200KHz	2MHz	5MHz, 8MHz, 10MHz	5MHz, 8MHz
Bus Width	4 bits	8 bits	8 bits	16 bits	8 bits
Number of Transistors	2,300 (10 microns)	3,500 (10 microns)	6,000 (6 microns)	29,000 (3 microns)	29,000 (3 microns)
Addressable Memory	640 bytes	16 KBytes	64 KBytes	1 MB	1 MB
Virtual Memory	--	--	--	--	--
Brief Description	First microcomputer chip, Arithmetic manipulation	Data/character manipulation	10X the performance of the 8008	10X the performance of the 8080	Identical to 8086 except for its 8-bit external bus

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1980s Processors

	80286	Intel386TM DX Microprocessor	Intel386TM SX Microprocessor	Intel486TM DX CPU Microprocessor
Introduced	2/1/82	10/17/85	6/16/88	4/10/89
Clock Speeds	6MHz, 8MHz, 10MHz, 12.5MHz	16MHz, 20MHz, 25MHz, 33MHz	16MHz, 20MHz, 25MHz, 33MHz	25MHz, 33MHz, 50MHz
Bus Width	16 bits	32 bits	16 bits	32 bits
Number of Transistors	134,000 (1.5 microns)	275,000 (1 micron)	275,000 (1 micron)	1.2 million (1 micron) (.8 micron with 50MHz)
Addressable Memory	16 megabytes	4 gigabytes	16 megabytes	4 gigabytes
Virtual Memory	1 gigabyte	64 terabytes	64 terabytes	64 terabytes
Brief Description	3-6X the performance of the 8086	First X86 chip to handle 32-bit data sets	16-bit address bus enabled low-cost 32-bit processing	Level 1 cache on chip

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1990s Processors

	Intel486TM SX Microprocessor	Pentium® Processor	Pentium® Pro Processor	Pentium® II Processor
Introduced	4/22/91	3/22/93	11/01/95	5/07/97
Clock Speeds	16MHz, 20MHz, 25MHz, 33MHz	60MHz,66MHz	150MHz, 166MHz, 180MHz, 200MHz	200MHz, 233MHz, 266MHz, 300MHz
Bus Width	32 bits	64 bits	64 bits	64 bits
Number of Transistors	1.185 million (1 micron)	3.1 million (.8 micron)	5.5 million (0.35 micron)	7.5 million (0.35 micron)
Addressable Memory	4 gigabytes	4 gigabytes	64 gigabytes	64 gigabytes
Virtual Memory	64 terabytes	64 terabytes	64 terabytes	64 terabytes
Brief Description	Identical in design to Intel486TM DX but without math coprocessor	Superscalar architecture brought 5X the performance of the 33-MHz Intel486TM DX processor	Dynamic execution architecture drives high-performing processor	Dual independent bus, dynamic execution, Intel MMXTM technology
Other Processor Family Members	Quick Reference Guide	Quick Reference Guide	Quick Reference Guide	Quick Reference Guide