Intel 80486
Sign in to saveThe 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.
Key facts
- CPU.name
- i486
- CPU.image
- upright=0.5|frameless|class=skin-invertframeless|upright=1
- CPU.caption
- The exposed die of an Intel 486DX2
- CPU.manuf1
- Intel, IBM, AMD, Texas Instruments, Harris Semiconductor, UMC, SGS Thomson
- CPU.designfirm
- Intel, with Pat Gelsinger as chief architect
- CPU.produced start
- April 10, 1989
- CPU.produced end
- September 28, 2007
- CPU.size from
- 1 μm
- CPU.size to
- 600 nm
- CPU.transistors
- 1.2–1.6 million
- CPU.slowest
- 16
- CPU.fastest
- 100
- CPU.fast unit
- MHz
- CPU.fsb slowest
- 16
- CPU.fsb slow unit
- MHz
- CPU.fsb fastest
- 50
- CPU.fsb fast unit
- MHz
- CPU.l1cache
- 8 KB to 16 KB
via Wikipedia infobox
Article
12 sectionsContents
- History
- Improvements
- Differences between i386 and i486
- Models
- Other makers of 486-like CPUs
- Motherboards and buses
- Obsolescence
- See also
- Notes
- Further reading
- References
- External links
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. The i387 FPU was a separate, optional math coprocessor installed in a motherboard socket alongside the i386.