CPU socket

File:Socket 370.JPG

Socket 370 processor socket

The term CPU socket (or CPU slot) is widely used to describe the connector linking the motherboard to the CPU(s) in certain types of desktop and server computers, particularly those compatible with the Intel x86 architecture.

Most CPU sockets and processors in use today are built around the pin grid array (PGA) architecture, in which the pins on the underside of the processor are inserted into the socket, usually with zero insertion force (ZIF) to aid installation. In contrast to this, several current and upcoming sockets use a land grid array (LGA) in which the pins are on the socket side instead and come in contact with pads on the processor. Slot based processors are cartridge shaped and fix into a slot that looks similar to expansion slots.

List of sockets and slots

Sockets

• Socket 1 - 80486
• Socket 2 - 80486
• Socket 3 - 80486 (3.3 V and 5 V) and compatibles
• Socket 4 - Intel Pentium 60/66 MHz
• Socket 5 - Intel Pentium 75-133 MHz; AMD K5; IDT WinChip C6, WinChip 2
• Socket 6 - 80486
• Socket 7 - Intel Pentium, Pentium MMX; AMD K6
• Super Socket 7 - AMD K6-2, AMD K6-III; Rise mP6
• Socket 8 - Intel Pentium Pro
• Socket 370 - Intel Pentium III, Celeron; Cyrix III; VIA C3
• Socket 423 - Intel Pentium 4¹ Willamette core
• Socket 463 (also known as Socket NexGen) - NexGen Nx586
• Socket 478 - Intel Pentium 4, Celeron, Pentium 4 Extreme Edition¹, Pentium M Socket N
• Socket 479 - Intel Pentium M, Celeron M, Core Duo, & Core Solo
• Socket 486 - 80486
• Socket 499 - DEC Alpha 21164a
• Socket 563 - AMD low-power mobile Athlon XP-M (µ-PGA Socket, mostly mobile parts)
• Socket 603 - Intel Xeon
• Socket 604 - Intel Xeon
• Socket 754 - AMD single-processor systems using single-channel DDR-SDRAM, including AMD Athlon 64, Sempron, Turion 64
• LGA 771 (also known as Socket 771) - Intel Xeon
• Socket T (also known as LGA 775 or Socket 775) - Intel Pentium 4, Pentium D, Celeron D, Pentium Extreme Edition, Core 2 Duo, Core 2 Extreme, Celeron¹
• Socket 939 - AMD single-processor systems using dual-channel DDR-SDRAM, including Athlon 64, Athlon 64 FX to 1 GHz², Athlon 64 X2, Opteron 100-series
• Socket 940 - AMD single and multi-processor systems using DDR-SDRAM, including AMD Opteron ², Athlon 64 FX
• Socket A (also known as Socket 462) - AMD Athlon, Duron, Athlon XP, Athlon XP-M, Athlon MP, and Sempron
• Socket F (also known as Socket 1207) - AMD multi-processor systems using DDR2-SDRAM, including AMD Opteron², replaces Socket 940
• Socket AM2 - AMD single-processor systems using DDR2-SDRAM, replaces Socket 754 and Socket 939²
• socket AM2+ - Future AMD Socket for single processor systems, support DDR2-SDRAM and HyperTransport 3 with separated power lanes. planned for mid 2007 to Q3 2007, replaces Socket AM2.
• Socket AM3 - Futrue AMD Socket for single processor systems, supports DDR3-SDRAM and HyperTransport 3 with separated power lanes. planned for mid 2008. and replace Socket AM2+ for those who want to go for DDR3-SDRAM
• Socket P - Future Intel-based, replaces Socket 479 for notebooks (Expected 2007)
• Socket S1 - AMD-based mobile platforms using DDR2-SDRAM, replaces Socket 754 in the mobile sector
• PAC418 - Intel Itanium
• PAC611 - Intel Itanium 2, HP PA-RISC 8800 and 8900
• Socket M - Intel Core Solo, Intel Core Duo, Intel Dual-Core Xeon and Intel Core 2 Duo
• Socket B - a new socket for future Intel CPUs incorporating the integrated memory controller and CSI (LGA 1366 contacts)
• Socket H - a replacement to the current Socket T (LGA 715 contacts)

Slots

• Slot 1 - Intel Celeron, Pentium II, Pentium III
• Slot 2 - Intel Pentium II Xeon, Pentium III Xeon
• Slot A - AMD Athlon
• Slot B - DEC Alpha
• Slotkets - adapters for using socket processors in bus-compatible slot motherboards

¹: The 478 pin socket was introduced because it uses a micro-PGA layout which is physically smaller than the socket 423. Socket 775 was introduced with support for PCI express, DDR2 memory and Intel's version of the AMD64 processor extensions (called EM64T), but also moved to the new Land Grid Array physical layout, where the pins are in the socket rather than on the CPU package, for better electrical performance.

²: These sockets are for CPUs with integrated memory controllers. The 754 pin models have a single memory channel routed through the CPU pins. The 939 pin models have two memory channels, hence the higher pin count. The 940 pin CPUs also have two memory channels but they require registered memory, and most have support for SMP. Sockets F and AM2 are redesigned to support DDR2. The Socket F contains 1207 pins (Added pins speculated to be for more scalability and better power distribution. Socket AM2 has 940 pin-holes but does not support current AMD Opteron processors.

³: The slot packages had two advantages; L2 cache could be installed on the processor package but on a separate piece of silicon, and insertion and removal is simpler and easier. However, it lengthens the path of the traces from the CPU to the chipset and so became unsuitable as clock speeds increased past around 500 MHz. They were therefore abandoned and replaced with Socket A/Socket 370.

See also

• List of Intel microprocessors
• List of AMD microprocessors

External links

• CPU Sockets Chart - A fairly detailed table listing x86 Sockets and associated attributes.
• techPowerUp! CPU Database