I486
family of 32-bit microprocessors introduced in 1989, including DX, SX and SL models
The Intel 486, officially named i486 and also known as 80486, is a microprocessor introduced in 1989. It is a higher-performance follow-up to the Intel 386. It represents the fourth generation of binary compatible CPUs following the 8086 of 1978, the Intel 80286 of 1982, and 1985's i386.
It was the first tightly-pipelined x86 design as well as the first x86 chip to include more than one million transistors. It offered a large on-chip cache and an integrated floating-point unit. When it was announced, the initial performance was originally published between 15 and 20 VAX MIPS, between 37,000 and 49,000 dhrystones per second, and between 6.1 and 8.2 double-precision megawhetstones per second for both 25 and 33 MHz version. A typical 50 MHz i486 executes 41 million instructions per second Dhrystone MIPS and SPEC integer rating of 27.9. It is approximately twice as fast as the i386 or i286 per clock cycle. The i486's improved performance is thanks to its five-stage pipeline with all stages bound to a single cycle. The enhanced FPU unit on the chip was significantly faster than the i387 FPU per cycle.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Jun 13, 2026. The linked authority identifier is Q213423. The Library of Congress control number is sh90005941. 1 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1989, 1978, 1982 and 1985.
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This entry incorporates text from “I486” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.