Difference between revisions of "Intel 80486"

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The '''Intel 80486''' is the successor to the [[Intel 80386]] in the [[Intel x86]] line of [[microprocessor]]s. It is basically the same [[Central Processing Unit|CPU]] as the 386, but includes the functionality of the [[Intel 80387]] [[floating point]] unit, and an 8K byte [[cache]].
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The '''Intel 80486''' is the successor to the [[Intel 80386]] in the [[Intel x86]] line of [[microprocessor]]s. It is basically the same [[Central Processing Unit|CPU]] as the 386, but includes an 8K byte [[cache]], and optionally (in the 80486DX model) the functionality of the [[Intel 80387]] [[floating point]] unit.
  
 
Implementation changes mean about half the [[instruction]]s execute in one clock cycle, instead of the two used in the 386, speeding it up considerably. Its [[main memory]] [[bus]] is 32 [[bit]]s wide, the same as the 386.`
 
Implementation changes mean about half the [[instruction]]s execute in one clock cycle, instead of the two used in the 386, speeding it up considerably. Its [[main memory]] [[bus]] is 32 [[bit]]s wide, the same as the 386.`
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It was offered in 25, 33, 50 and 66 MHz versions; a 100 MHz version was demonstrated in 1990. For the 80486SX model, the 80487SX numeric [[co-processor]] is available.
  
 
Its replacement was the [[Intel Pentium]].
 
Its replacement was the [[Intel Pentium]].
  
 
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Revision as of 20:22, 8 September 2018

The Intel 80486 is the successor to the Intel 80386 in the Intel x86 line of microprocessors. It is basically the same CPU as the 386, but includes an 8K byte cache, and optionally (in the 80486DX model) the functionality of the Intel 80387 floating point unit.

Implementation changes mean about half the instructions execute in one clock cycle, instead of the two used in the 386, speeding it up considerably. Its main memory bus is 32 bits wide, the same as the 386.`

It was offered in 25, 33, 50 and 66 MHz versions; a 100 MHz version was demonstrated in 1990. For the 80486SX model, the 80487SX numeric co-processor is available.

Its replacement was the Intel Pentium.