Editing intel/80486

{{intel title|80486}}
{{ic family
| title             = Intel 80486
| image             = Intel i486 DX 25MHz SX328.jpg
| caption           = Intel A80486DX-25
| developer         = Intel
| manufacturer      = Intel
| type              = Microprocessors
| first announced   = April 10, 1989
| first launched    = June, 1989
| production start  = 1988
| production end    = 2007
| arch              = x86
| isa               = IA-32
| microarch         = 80486
| word              = 32 bit
| proc              = 1 µm
| proc 2            = 800 nm
| proc 3            = 600 nm
| tech              = CMOS
| clock min         = 16 MHz
| clock max         = 100 MHz
| package           = PGA-168
| package 2         = PQFP-196
| package 3         = SQFP-208
| succession       = yes
| predecessor      = 80386
| predecessor link = intel/80386
| successor        = Pentium
| successor link   = intel/pentium
}}
The '''80486''', also '''i486''' and '''486''', (pronounced ''eighty-four-eighty-six'') was a family of {{arch|32}} 4th-generation [[x86]] microprocessors introduced by [[Intel]] in [[1989]] as a successor to the {{intel|80386}}. 486 introduced a number of enhancements to 386 including a new level 1 cache, better IPC performance, and an integrated [[FPU]]. The 486 became the first [[x86]] chip family to exceed one million transistors.

== Architecture ==
{{main|intel/microarchitectures/80486|l1=80486 Microarchitectures}}
Like {{\\|80386|its predecessor}}, the 80486 maintains full backwards [[object code]] comparability with the all previous [[x86]] processors ({{\\|80386}}, {{\\|80286}},  {{\\|80186}}, etc...). To improve performance Intel introduced a new layer of cache on-die (previously various external extensions existed). The 8 KB, 4-way set associative, write-back policy, cache was unified for both the data and instructions. This provided much needed faster access to recently used data and instructions. Various enhancements were also made to the bus interface including faster communication that required single clock cycle instead of multiple.

Whereas before a separately packaged [[FPU|math]] [[coprocessor]] was used (i.e. {{\\|80387}}, {{\\|80287}}, etc..), the 80486 moved the unit on-die eliminating the external communication delays altogether. Furthermore more aggressive math algorithms were used to implement the new [[FPU]] yielding faster floating point calculations.

The pipeline itself received some attention as well. Simple ALU ''register, register'' and ''register, [[immediate value|immediate]]'' cached operations could now complete in a single cycle; this {{\\|80386|previously}} required at least 2 cycles.

== Members ==

=== i486DX ===
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           This table is generated automatically from the data in the actual articles.
           If a microprocessor is missing from the list, an appropriate article for it needs to be
           created and tagged accordingly.

           Missing a chip? please dump its name here: http://en.wikichip.org/wiki/WikiChip:wanted_chips
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<table class="wikitable sortable">
<tr><th colspan="16" style="background:#D6D6FF;">i487DX Processors</th></tr>
<tr><th>Model</th><th>Launched</th><th>Process</th><th>Freq</th><th>Max Mem</th></tr>
{{#ask: [[Category:microprocessor models by intel]][[instance of::microprocessor]][[microprocessor family::80486]][[core name::~486DX*]]
 |?full page name
 |?model number
 |?first launched
 |?process
 |?base frequency#MHz
 |?max memory#GB
 |format=template
 |template=proc table 2
 |userparam=6
 |mainlabel=-
}}
{{table count|col=16|ask=[[Category:microprocessor models by intel]][[instance of::microprocessor]][[microprocessor family::80486]][[core name::~486DX*]]}}
</table>

=== i486SX ===
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           This table is generated automatically from the data in the actual articles.
           If a microprocessor is missing from the list, an appropriate article for it needs to be
           created and tagged accordingly.

           Missing a chip? please dump its name here: http://en.wikichip.org/wiki/WikiChip:wanted_chips
-->
<table class="wikitable sortable">
<tr><th colspan="16" style="background:#D6D6FF;">i486SX Processors</th></tr>
<tr><th>Model</th><th>Launched</th><th>Process</th><th>Freq</th><th>Max Mem</th></tr>
{{#ask: [[Category:microprocessor models by intel]][[instance of::microprocessor]][[microprocessor family::80486]][[core name::~486SX*]]
 |?full page name
 |?model number
 |?first launched
 |?process
 |?base frequency#MHz
 |?max memory#GB
 |format=template
 |template=proc table 2
 |userparam=6
 |mainlabel=-
}}
{{table count|col=16|ask=[[Category:microprocessor models by intel]][[instance of::microprocessor]][[microprocessor family::80486]][[core name::~486SX*]]}}
</table>

=== i486SL ===
<!-- NOTE: 
           This table is generated automatically from the data in the actual articles.
           If a microprocessor is missing from the list, an appropriate article for it needs to be
           created and tagged accordingly.

           Missing a chip? please dump its name here: http://en.wikichip.org/wiki/WikiChip:wanted_chips
-->
<table class="wikitable sortable">
<tr><th colspan="16" style="background:#D6D6FF;">i486SL Processors</th></tr>
<tr><th>Model</th><th>Launched</th><th>Process</th><th>Freq</th><th>Max Mem</th></tr>
{{#ask: [[Category:microprocessor models by intel]][[instance of::microprocessor]][[microprocessor family::80486]][[core name::~486SL*]]
 |?full page name
 |?model number
 |?first launched
 |?process
 |?base frequency#MHz
 |?max memory#GB
 |format=template
 |template=proc table 2
 |userparam=6
 |mainlabel=-
}}
{{table count|col=16|ask=[[Category:microprocessor models by intel]][[instance of::microprocessor]][[microprocessor family::80486]][[core name::~486SL*]]}}
</table>

=== i486GX ===
<!-- NOTE: 
           This table is generated automatically from the data in the actual articles.
           If a microprocessor is missing from the list, an appropriate article for it needs to be
           created and tagged accordingly.

           Missing a chip? please dump its name here: http://en.wikichip.org/wiki/WikiChip:wanted_chips
-->
<table class="wikitable sortable">
<tr><th colspan="16" style="background:#D6D6FF;">i486GX Processors</th></tr>
<tr><th>Model</th><th>Launched</th><th>Process</th><th>Freq</th><th>Max Mem</th></tr>
{{#ask: [[Category:microprocessor models by intel]][[instance of::microprocessor]][[microprocessor family::80486]][[core name::~486GX*]]
 |?full page name
 |?model number
 |?first launched
 |?process
 |?base frequency#MHz
 |?max memory#GB
 |format=template
 |template=proc table 2
 |userparam=6
 |mainlabel=-
}}
{{table count|col=16|ask=[[Category:microprocessor models by intel]][[instance of::microprocessor]][[microprocessor family::80486]][[core name::~486GX*]]}}
</table>

== Clones ==
* {{amd|Am486}}
{{expand list}}

== Documents ==

=== Datasheet ===
* [[:File:486 DX2 Microprocessor Data Book (February 1992).pdf|486 DX2 Microprocessor Data Book (February 1992)]]
* [[:File:Intel486 DX2 Microprocessor Data Book (July 1992).pdf|Intel486 DX2 Microprocessor Data Book (July 1992)]]
* [[:File:486 DX Microprocessor Data Book (October 1992).pdf|486 DX Microprocessor Data Book (October 1992)]]
* [[:File:i486 MICROPROCESSOR (April 1989).pdf|i486 MICROPROCESSOR (April 1989)]]

=== Manual ===
* [[:File:Intel486 Microprocessor Family Programmer's Reference Manual (1992).pdf|Intel486 Microprocessor Family Programmer's Reference Manual (1992)]]
* [[:File:i486 MICROPROCESSOR PROGRAMMER'S REFERENCE MANUAL (1990).pdf|i486 MICROPROCESSOR PROGRAMMER'S REFERENCE MANUAL (1990)]]
* [[:File:i486 MICROPROCESSOR HARDWARE REFERENCE MANUAL (1990).pdf|i486 MICROPROCESSOR HARDWARE REFERENCE MANUAL (1990)]]
designer	Intel +
first announced	April 10, 1989 +
first launched	June 1989 +
full page name	intel/80486 +
instance of	microprocessor family +
instruction set architecture	IA-32 +
main designer	Intel +
manufacturer	Intel +
microarchitecture	80486 +
name	Intel 80486 +
package	PGA-168 +, PQFP-196 + and SQFP-208 +
process	1,000 nm (1 μm, 0.001 mm) +, 800 nm (0.8 μm, 8.0e-4 mm) + and 600 nm (0.6 μm, 6.0e-4 mm) +
technology	CMOS +
word size	32 bit (4 octets, 8 nibbles) +