Socket A is the CPU socket

CPU socket

A CPU socket or CPU slot is a mechanical component that provides mechanical and electrical connections between a microprocessor and a printed circuit board . This allows the CPU to be replaced without soldering....

 used for AMD processors

Central processing unit

The central processing unit is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in...

 ranging from the Athlon Thunderbird to the Athlon XP/MP 3200+, and AMD budget processors including the Duron

Duron

The AMD Duron was an x86-compatible microprocessor manufactured by AMD. It was released on June 19, 2000 as a low-cost alternative to AMD's own Athlon processor and the Pentium III and Celeron processor lines from rival Intel...

 and Sempron

Sempron

Sempron has been the marketing name used by AMD for several different budget desktop CPUs, using several different technologies and CPU socket formats. The Sempron replaced the AMD Duron processor and competes against Intel's Celeron series of processors...

. Socket A also supports AMD Geode NX embedded processors (derived from the Mobile Athlon XP). The socket is a zero insertion force pin grid array

Pin grid array

A pin grid array, often abbreviated PGA, is a type of integrated circuit packaging. In a PGA, the package is square or roughly square, and the pins are arranged in a regular array on the underside of the package...

 type with 453 pins (nine pins are blocked in the socket to prevent accidental insertion of Socket 370

Socket 370

Socket 370 is a common format of CPU socket first used by Intel for Pentium III and Celeron processors to replace the older Slot 1 CPU interface on personal computers. The "370" refers to the number of pin holes in the socket for CPU pins...

 CPUs, hence the number 462). The front side bus frequencies supported for the AMD Athlon XP and Sempron are 133 MHz, 166 MHz, and 200 MHz.
Socket A supports 32-bit CPUs only.

Socket A was replaced by Socket 754

Socket 754

Socket 754 is a CPU socket originally developed by AMD to succeed its Athlon XP platform . Socket 754 was the first socket developed by AMD to support their new consumer version of the 64 bit microprocessor family known as AMD64.-Technical specifications:Socket 754 was the original socket for...

 and Socket 939

Socket 939

Socket 939 is a CPU socket released by AMD in June 2004 to supersede the previous Socket 754 for Athlon 64 processors. Socket 939 was succeeded by Socket AM2 in May 2006. It is the second socket designed for AMD's AMD64 range of processors.-Availability:...

 during 2003 and 2004 respectively, except for its use with Geode NX processors.

Technical specifications

• Support of processor clock-speeds between 600 MHz (Duron) to 2333 MHz (Athlon XP 3200+)
• Double data rate
  Double data rate
  In computing, a computer bus operating with double data rate transfers data on both the rising and falling edges of the clock signal. This is also known as double pumped, dual-pumped, and double transition....
  
   100, 133, 166 and 200 MHz front side bus
  Front side bus
  A front-side bus is a computer communication interface often used in computers during the 1990s and 2000s.It typically carries data between the central processing unit and a memory controller hub, known as the northbridge....
  
   on Duron, XP and Sempron processors, based on the Alpha 21264
  Alpha 21264
  The Alpha 21264 was a Digital Equipment Corporation RISC microprocessor introduced in October, 1996. The 21264 implemented the Alpha instruction set architecture .- Description :...
  
   EV6 bus.

Initially launched with 100 MHz FSB support in the earliest chipsets it evolved stepwise to faster 200 MHz FSB while maintaining pin compatibility throughout its lifetime. However, clock, timing, BIOS and voltage differences restrict compatibility between older chipsets and later processors.

Socket A mechanical load limits

AMD recommends that the mass of a Socket A CPU cooler to not exceed 300 gram

Gram

The gram is a metric system unit of mass....

s (10.6 ounce

Ounce

The ounce is a unit of mass with several definitions, the most commonly used of which are equal to approximately 28 grams. The ounce is used in a number of different systems, including various systems of mass that form part of the imperial and United States customary systems...

s). Heavier coolers may result in damage to the die

Die (integrated circuit)

A die in the context of integrated circuits is a small block of semiconducting material, on which a given functional circuit is fabricated.Typically, integrated circuits are produced in large batches on a single wafer of electronic-grade silicon or other semiconductor through processes such as...

 when the system is not properly handled.

All socket A processors (Athlon, Sempron, Duron and Geode NX) have the following mechanical maximum load limits which should not be exceeded during heatsink assembly, shipping conditions, or standard use. Load above those limits may crack the processor die and make it unusable.

Location	Dynamic	Static
Die Surface	445 N(100 lbf Pound-force The pound force is a unit of force in some systems of measurement including English engineering units and British gravitational units.- Definitions :... )	133 N(30 lbf Pound-force The pound force is a unit of force in some systems of measurement including English engineering units and British gravitational units.- Definitions :... )
Die Edge	44 N(10 lbf Pound-force The pound force is a unit of force in some systems of measurement including English engineering units and British gravitational units.- Definitions :... )	44 N(10 lbf Pound-force The pound force is a unit of force in some systems of measurement including English engineering units and British gravitational units.- Definitions :... )

Those load limits are quite small compared to the load limits of Socket 478

Socket 478

Socket 478 is a 478-contact CPU socket used for Intel's Pentium 4 and Celeron series CPUs.Socket 478 was launched with the Northwood core to compete with AMD's 462-pin Socket A and their Athlon XP processors. Socket 478 was intended to be the replacement for Socket 423, a Willamette-based...

processors. Indeed, they were so small that many users ended up with cracked processors while trying to remove or attach heatsinks for their fragile processors. This made installing non-standard or non-certified heatsink solutions a risky business.