Editing Socket A

{{Short description|CPU socket for old AMD CPUs}}
{{Use mdy dates|date=November 2022}}
{{CPU socket
| name        = Socket 462 / A
| image       = [[Image:Socket 462.jpg|290px]]
| formfactors = {{ubl|[[Ceramic Pin Grid Array]] ([[Ceramic pin grid array|CPGA]])|[[Organic Pin Grid Array]] ([[OPGA]])}}
| type        = [[Pin grid array|PGA]]-[[Zero insertion force|ZIF]]
| contacts    = 462
| protocol    = EV6
| fsb         = 200 MT/s, 266 MT/s, 333 MT/s, 400 MT/s
| voltage     = 1.0–2.05V
| dimensions  = 
| processors  = {{ubl|[[AMD]] [[Athlon]] (600–1400&nbsp;MHz)|[[Advanced Micro Devices|AMD]] [[Athlon#Athlon XP/MP|Athlon XP]] (850–2333&nbsp;MHz)|[[Advanced Micro Devices|AMD]] [[Duron]] (600–1800&nbsp;MHz)|[[Advanced Micro Devices|AMD]] [[Sempron]] (1500–2200&nbsp;MHz)|[[Advanced Micro Devices|AMD]] [[Athlon#Athlon XP/MP|Athlon MP]] (1000–2133&nbsp;MHz)|[[Advanced Micro Devices|AMD]] [[Geode (processor)#Geode NX|Geode NX]] (667–1800&nbsp;MHz)}}
| predecessor = [[Slot A]]
| successor   = {{ubl|[[Socket 754]]|[[Socket 939]]|[[Socket 940]]}}
|release-date=2000-06|memory=DDR}}

'''Socket A''' (also known as '''Socket 462''') is a [[zero insertion force]] [[pin grid array]] (PGA) [[CPU socket]] used for [[AMD]] [[Central processing unit|processors]] ranging from the [[Athlon Thunderbird#Athlon Thunderbird (2000–2001)|Athlon Thunderbird]] to the [[Athlon#Athlon XP/MP|Athlon XP/MP]] 3200+, and AMD budget processors including the [[Duron]] and [[Sempron]]. Socket A also supports AMD [[Geode (processor)#Geode NX|Geode NX]] embedded processors (derived from the [[Athlon#Mobile Athlon XP|Mobile Athlon XP]]). It compliments (and later supersedes) the prior [[Slot A]] CPU interface used in some Athlon Thunderbird processors. The front-side bus frequencies supported for the AMD Athlon XP and Sempron are 133&nbsp;[[MHz]], 166&nbsp;MHz, and 200&nbsp;MHz. Socket A supports 32-bit CPUs only.

The socket is a [[zero insertion force]] [[pin grid array]] type with 462 pins, hence the alternative name Socket 462. About nine pins in the socket are blocked to discourage accidental insertion of [[Socket 370]] CPUs on Socket A motherboards.

Socket A was replaced by [[Socket 754]] and [[Socket 939]] during 2003 and 2004 respectively, except for its use with Geode NX processors.

== Technical specifications ==
* Support of processor clock-speeds between 600&nbsp;MHz (Duron) to 2333&nbsp;MHz (Athlon XP 3200+)<ref>{{cite web |title=CPU Sockets Chart |url=http://www.pchardwarelinks.com/sockets.htm |website=PC Hardware Links |access-date=April 4, 2009}}</ref>
* [[Double data rate]] 100, 133, 166 and 200&nbsp;MHz [[front-side bus]] on Duron, XP and Sempron processors, based on the [[Alpha 21264]] EV6 bus.
[[File:Underside of an 800 MHz Athlon CPU.jpg|thumb|left|Socket 462 of an 800 MHz Athlon CPU]] 
Initially launched with 100&nbsp;MHz FSB support in the earliest chipsets it evolved stepwise to faster 200&nbsp;MHz FSB while maintaining pin compatibility throughout its lifetime. However, clock, timing, BIOS and voltage differences restrict compatibility between older chipsets and later processors.<ref>{{Cite web |title=CTechnology Evolution |url=https://www.amd.com/us-en/Processors/ProductInformation/0,,30_118_9331_12851,00.html |website=AMD |language=en-US |access-date=April 4, 2009}}</ref>

Socket dimensions are 5.59 cm (5.24 cm without lever) × 6.55 cm or 2.2" (2.06" without lever) × 2.58", slightly bigger than Socket 370 sockets.

== Heatsink ==
Heatsinks were commonly attached directly to the CPU socket, but some motherboards also had 4 holes for fastening bigger heatsinks to the motherboard. Those holes are placed in a rectangle with lateral lengths of 35 mm and 65 mm.

== Socket A mechanical load limits ==
[[File:Cracked die corner.jpg|thumb|The corners of the exposed CPU dies were susceptible to damage like shown here when coolers were installed incorrectly or systems were handled roughly.]]
AMD recommends that the mass of a Socket A CPU cooler to not exceed 300&nbsp;[[gram]]s (10.6&nbsp;[[ounce]]s). Heavier coolers may result in damage to the [[Die (integrated circuit)|die]] when the system is not properly handled.

All Socket A processors (Athlon, Sempron, Duron and Geode NX) have the following mechanical maximum load limits<ref>{{cite web |title=AMD Athlon Processor Model 4 Data Sheet |url=https://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/23792.pdf |website=AMD |language=en-US |access-date=November 8, 2001 |url-status=unfit |archive-url=https://web.archive.org/web/20050407201323/http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/23792.pdf |archive-date=April 7, 2005}}</ref> which should not be exceeded during heatsink assembly, shipping conditions, or standard use. They came with a warning that load above those limits may crack the processor die and make it unusable. The limits are included in the table below.
{| class="wikitable" style="font-size: 100%; text-align: center;"
|-
! style="width:12em;" | Location
! Dynamic
! Static
|-
| Die Surface
| 445&nbsp;[[newton (unit)|N]] (100&nbsp;[[Pound-force|lb<sub>f</sub>]])
| 133&nbsp;[[newton (unit)|N]] (30&nbsp;[[Pound-force|lb<sub>f</sub>]])
|-
| Die Edge
| 44&nbsp;[[newton (unit)|N]] (10&nbsp;[[Pound-force|lb<sub>f</sub>]])
| 44&nbsp;[[newton (unit)|N]] (10&nbsp;[[Pound-force|lb<sub>f</sub>]])
|}
These load limits are quite small compared to the load limits of [[Socket 370]], [[Socket 423]] and [[Socket 478]] processors. Indeed, they were so small that many users more often than not ended up with cracked processors while trying to remove or attach heatsinks to their fragile processor core. This makes installing non-standard or non-certified heatsink solutions a risky business.{{Citation needed|date=October 2013}} [[OEM]] aluminium heatsinks typically provided smaller thermal tolerances, so the improper application or absence of a thermal pad or thermal grease or operation in high room temperatures may result in some Socket A CPUs [[Overheating (electricity)|overheating]] and [[Crash (computing)|crashing]], permanently damaging them and rendering them unusable.

== Chipsets==
AMD offered official chipsets for the Slot A/Socket A CPUs. These are included in the table below.
{| class="wikitable" style="text-align: center;"
! Model 
! Code name 
! Released 
! CPU support 
! [[Front-side bus|FSB]]/[[HyperTransport|HT]] (MHz) 
! Southbridge 
! Features / Notes
|-
! AMD-750 chipset
| AMD-751 
| August 1999<ref>{{cite web |title=AMD-750 Chipset Overview |url=http://www.datasheetcatalog.org/datasheet/AdvancedMicroDevices/mXvvyt.pdf |website=AMD |language=en-US |access-date=August 1, 2001}}</ref> 
| [[Athlon]], [[Duron]]&nbsp;([[Slot&nbsp;A]], [[Socket&nbsp;A]]), [[Alpha&nbsp;21264]]{{Citation needed|date=November 2023}} 
| 50 (100MT/s) 
| AMD-756, VIA-VT82C686A 
| align="left" | AGP&nbsp;2×, SDRAM<br />''Irongate'' chipset family; early steppings had issues with AGP&nbsp;2×; drivers often limited support to AGP&nbsp;1×; later fixed with "super bypass" memory access adjustment.<ref>{{Cite web |last=Orozco |first=Silvino |date=December 29, 1999 |title=AMD's Super Bypass - AMD Improves their 750 Chipset |url=http://www.tomshardware.com/reviews/amd,155.html |website=Tom's Hardware |language=en-US |access-date=November 11, 2022}}</ref>
|-
! AMD-760 chipset
| AMD-761 
| Nov 2000 
| Athlon, Athlon&nbsp;XP, Duron&nbsp;([[Socket&nbsp;A]]), [[Alpha&nbsp;21264]]{{Citation needed|date=November 2023}} 
| 66 (133MT/s) 
| AMD-766, VIA-VT82C686B 
| align="left" | AGP&nbsp;4×, DDR SDRAM
|}

Third-party chipsets include the [[nForce]], [[nForce2]], and a large number of [[List_of_VIA_chipsets#Slot_A_and_Socket_A|VIA K-series]] chipsets.

In practice, third-party chipsets were heavily favoured by motherboard manufacturers. Stability problems and compatibility quirks from these chipsets abounded from manufacturers not following chipset designers' guidelines. This caused long-lasting damage to AMD's reputation, despite AMD having nothing to do with the poorly-realised hardware.{{cn|date=August 2023}} A similar incident happened with third-party chipsets for [[Super Socket 7]] CPUs, of which AMD tried to remedy it by putting [[quality assurance]] measures for the Athlon, which used Slot A/Socket A CPUs. Despite this, however, the aforementioned problems mentioned above still lingered on for quite a while, even for Athlon CPUs.

== See also ==
* [[List of AMD microprocessors]]

== References ==
{{Commons category|Socket A}}
{{Reflist}}

{{amdsock}}

[[Category:AMD sockets]]