CPU socket
A CPU socket or CPU slot is an electrical component that attaches to a printed circuit board (PCB) and is designed to house a microprocessor. It is a special type of integrated circuit socket designed for very high pin counts. A CPU socket provides many functions, including providing a physical structure to support the CPU, providing support for a heatsink, facilitating replacement (as well as reducing cost) and most importantly forming an electrical interface both with the CPU and the PCB. CPU sockets can most often be found in most desktop and server computers (laptops typically use surface mount CPUs), particularly those based on the Intel x86 architecture on the motherboard.
Interface types
CPU socket structure is largely dependent on the packaging of the CPU it is designed to house. Most CPUs are based on the pin grid array (PGA) architecture in which short, stiff pins are arranged in a grid on the underside of the processor are mated with holes in the socket. To minimize the risk of bent pins, zero insertion force (ZIF) sockets allow the processor to be inserted without any resistance and then lock in place with a lever or latch mechanism.
As of 2007[update], land grid array (LGA) packages have started to supplant PGA with most modern CPU designs using this scheme. The term LGA "socket" is actually a bit of a misnomer. With LGA sockets, the socket contains pins that make contact with pads or lands on the bottom of the processor package. While not popular for many years, LGAs are not new, microprocessors since the mid-1990s have used them.
In the late 1990s, many x86 processors fit into slots, rather than sockets. CPU slots are single-edged connectors similar to expansion slots, into which a PCB holding a processor is inserted. Slotted CPU packages offered two advantages: L2 cache memory size could be packaged with the CPU rather than the motherboard and processor insertion and removal was often easier. However, they proved to have performance limitations and once it was possible to place larger cache memory directly on the CPU die the industry reverted back to sockets.
Function
A CPU socket is often made up of plastic, a metal lever or latch and metal contacts for each of the pins or lands on the CPU. Most packages are keyed to ensure the proper insertion of the CPU. CPUs with a PGA package are inserted into the socket and the latch is closed. This has the effect of physically securing and protecting the CPU as well as causing an electrical connection between all the CPU pins and the socket. In the case of LGA the CPU is placed onto the socket and a latch is closed over the CPU, securing it. Most CPU sockets are designed to support the installation of a heatsink. It must be able to protect the CPU from the weight of the heatsink (often very heavy in weight relative to the CPU) particularly during the installation and removal, but also ensuring the heatsink makes good thermal contact with the CPU.
CPU sockets provide an advantage over directly attaching CPUs to the PCB by making it easier to replace the processor in the event of a failure. The CPU is often the most expensive component in the system and the cost of a CPU socket is relatively low which makes this popular among computer system manufacturers.
The nature of a CPU socket requires it to not only make good electrical contact with the CPU, but must also be solderable to the PCB with which it interfaces.[1]
List of sockets and slots
Many socket names containing three- or four-digit numbers represent the number of pins on the processor or socket.
| Socket name |
Year of introduction | Year of EOL | CPU families | Package | Pin count | Pin pitch | Bus speed | Notes | |
|---|---|---|---|---|---|---|---|---|---|
| DIP | 1970s | Still available | Intel 8086 Intel 8088 |
DIP | 40 | 2.54mm | 5/10MHz | ||
| PLCC | ? | Still available | Intel 80186 Intel 80286 Intel 80386 |
PLCC | 68, 132 | 1.27mm | 6-40MHz | ||
| Socket 1 | 1989 | ? | Intel 80486 | PGA | 169 | ? | ? | ||
| Socket 2 | ? | ? | Intel 80486 | PGA | 238 | ? | ? | ||
| Socket 3 | 1991 | ? | Intel 80486 | PGA | 237 | ? | ? | ||
| Socket 4 | ? | ? | Intel Pentium | PGA | 273 | ? | ? | ||
| Socket 5 | ? | ? | Intel Pentium AMD K5 IDT WinChip C6 IDT WinChip 2 |
PGA | 320 | ? | ? | ||
| Socket 6 | ? | ? | Intel 80486 | PGA | 235 | ? | ? | ||
| Socket 7 | 1994 | ? | Intel Pentium Intel Pentium MMX AMD K6 |
PGA | 321 | ? | 50-66MHz | ||
| Super Socket 7 | 1998 | ? | AMD K6-2 AMD AMD K6-III Rise mP6 Cyrix MII |
PGA | 321 | ? | 66-100MHz | ||
| Socket 8 | 1995 | ? | Intel Pentium Pro | PGA | 387 | ? | 60-66MHz | ||
| Slot 1 | 1997 | ? | Intel Pentium II Intel Pentium III |
Slot | 242 | ? | 66-133MHz | Celeron (Covington, Mendocino) Pentium II (Klamath) Pentium III (Katmai)- all versions Pentium III (coppermine) | |
| Slot 2 | 1998 | ? | Intel Pentium II Xeon | Slot | 330 | ? | 100-133MHz | ||
| Socket 463/ Socket NexGen |
? | ? | NexGen Nx586 | PGA | 463 | ? | ? | ||
| Socket 499 | ? | ? | Alpha 21164A | Slot | 587 | ? | ? | ||
| Slot A | 1999 | ? | AMD Athlon | Slot | 242 | ? | 100MHz | ||
| Slot B | ? | ? | Alpha 21264 | Slot | 587 | ? | ? | ||
| Socket 370 | 1999 | ? | Intel Pentium III Intel Celeron VIA Cyrix III VIA C3 |
PGA | 370 | 1.27mm[2] | 66-133MHz | ||
| Socket 462/ Socket A |
2000 | ? | AMD Athlon AMD Duron AMD Athlon XP AMD Athlon XP-M AMD Athlon MP AMD Sempron |
PGA | 462 | ? | 100-200MHz This is a double data rate bus having a 400 MT/s
(megatransfers/second) fsb in the later models |
||
| Socket 423 | 2000 | ? | Intel Pentium 4 | PGA | 423 | 1mm[3] | 400 MT/s (100 MHz) | Willamette core only | |
| Socket 478/ Socket N |
2000 | ? | Intel Pentium 4 Intel Celeron Intel Pentium 4 EE Intel Pentium M |
PGA | 478 | 1.27mm[4] | 400-800 MT/s (100-200 MHz) | ||
| Socket 495 | 2000 | ? | Intel Celeron | PGA | 495 | 1.27mm[5] | ? | ||
| PAC418 | 2001 | ? | Intel Itanium | PGA | 418 | ? | 133MHz | ||
| Socket 603 | 2001 | ? | Intel Xeon | PGA | 603 | 1.27mm[6] | 400-533 MT/s (100-133 MHz) | ||
| PAC611 | 2002 | ? | Intel Itanium 2 HP PA-8800, PA-8900 |
PGA | 611 | ? | ? | ||
| Socket 604 | 2002 | ? | Intel Xeon | PGA | 604 | 1.27mm[7] | 400-1066 MT/s (100-266 MHz) | ||
| Socket 754 | 2003 | ? | AMD Athlon 64 AMD Sempron AMD Turion 64 |
PGA | 754 | 1.27mm[8] | 200-800MHz | ||
| Socket 940 | 2003 | ? | AMD Opteron Athlon 64 FX | PGA | 940 | 1.27mm[9] | 200-1000MHz | ||
| Socket 479 | 2003 | ? | Intel Pentium M Intel Celeron M |
PGA | 479[10] | ? | 400-533 MT/s (100-133 MHz) | ||
| Socket 939 | 2004 | 11/2008 | AMD Athlon 64 AMD Athlon 64 FX AMD Athlon 64 X2 AMD Opteron |
PGA | 939 | 1.27mm[11] | 200-1000MHz | Support of Athlon 64 FX to 1 GHz Support of Opteron limited to 100-series only | |
| LGA 775/ Socket T |
2004 | ? | Intel Pentium 4 Intel Pentium D Intel Celeron Intel Celeron D Intel Pentium XE Intel Core 2 Duo Intel Core 2 Quad Intel Xeon |
LGA | 775 | 1.09mm x 1.17mm[12] | 1600MHz | ||
| Socket 563 | ? | ? | AMD Athlon XP-M | PGA | 563 | ? | ? | ||
| Socket M | 2006 | ? | Intel Core Solo Intel Core Duo Intel Dual-Core Xeon Intel Core 2 Duo |
PGA | 478 | ? | 533 - 667 MT/s (133-166 MHz) | For notebook platform Replaces Socket 479 | |
| LGA 771/ Socket J |
2006 | ? | Intel Xeon | LGA | 771 | 1.09mm x 1.17mm[13] | 1600 MHz | ||
| Socket S1 | 2006 | ? | AMD Turion 64 X2 | PGA | 638 | 1.27mm[14] | 200-800MHz | ||
| Socket AM2 | 2006 | ? | AMD Athlon 64 AMD Athlon 64 X2 |
PGA | 940 | 1.27mm[15] | 200-1000MHz | Replaces Socket 754 and Socket 939 | |
| Socket F | 2006 | ? | AMD Athlon 64 FX AMD Opteron |
LGA | 1207 | 1.1mm[16] | ? | Replaces Socket 940 | |
| Socket AM2+ | 2007 | ? | AMD Athlon 64 AMD Athlon X2 AMD Phenom |
PGA | 940 | 1.27mm[17] | 200-2600MHz | Separated power planes Replaces Socket AM2 AM2+ Pkg. CPU's can work in Socket AM2 AM2 Pkg. CPU's can work in Socket AM2+ | |
| Socket P | 2007 | ? | Intel Core 2 | PGA | 478 | 533-1066 MT/s (133-266 MHz) | For notebook platform Replaces Socket M | ||
| Socket 441 | 2008 | ? | Intel Atom | PGA | 441 | ? | 400-667MHz | ||
| LGA 1366/ Socket B |
2008 | ? | Intel Core i7 | LGA | 1366 | 4.8-6.4 GT/s | Replaces server-oriented Socket J (LGA 771) in the entry level. | ||
| Socket AM3 | 2009 | ? | AMD Phenom II AMD Athlon II AMD Sempron |
PGA | 941[18] | 1.27mm[19] | 200-3200MHz | Separated power planes Replaces Socket AM2+ AM3 Pkg. CPU's can work in Socket AM2/AM2+ Sempron 140 Only | |
| LGA 1156/ Socket H |
2009 | ? | Intel Core i7 Intel Core i5 Intel Core i3 |
LGA | 1156 | ? | 2.5 GT/s | DMI bus is a (perhaps modified) PCI-E x4 v1.1 interface Only 800 series of Core i7 are Socket 1156 |
Future products
These sockets have been announced or are rumored to be used in upcoming computing platforms.
| Socket name |
Year of Introduction | Year of EOL | CPU families | Package | Pin count | Bus speed | Notes |
|---|---|---|---|---|---|---|---|
| Socket FS1 | ? | ? | AMD | ? | ? | ? | Future product. Announced, but not released. |
| Socket G34 | Q1 2010 (planned) | ? | AMD | LGA | 1974 | 3.2 GHz HT3 | Future product. Announced, but not released. Will be used for the Opteron 6000 series CPUs. |
| Socket C32 | Q2 2010 (planned) | ? | AMD | LGA | 1207 | 3.2 GHz HT3 | Future product. Announced, but not released. Will be used for the Opteron 4000 series CPUs. |
| LGA 1155/Socket H2 | Q1 2011 (planned) | ? | Intel | LGA | 1155 | ? | Future product. Announced, but not released. Will be used for Sandy Bridge-based desktop CPUs in 2011. IGP built into the core instead of a separate chip. |
| LGA 1356/Socket B2 | Q3 2011 (planned) | ? | Intel | LGA | 1356 | ? | Future product. Announced, but not released. Will be used for Sandy Bridge-based desktop CPUs in 2011. Geared towards high-end desktop builds. |
| LGA 2011/Socket R | Q3 2011 (planned) | ? | Intel | LGA | 2011 | ? | Future product. Announced, but not released. Will be used for Sandy Bridge-'E'/Patsburg-based CPUs in 2011. PCI Express 3.0 - 32 lanes Four channel DDR3 memory controller. |
| Socket AM3 Revision 2 | 2011 (planned) | ? | AMD | PGA | 941 | ? | Future product. Announced, but not released. Is intended to support the upcoming Bulldozer-based desktop CPUs in 2011. |
Slotkets
Slotkets are special adapters for using socket processors in bus-compatible slot motherboards.
Notes and References
- ^ "LGA Sockets". Amphenol. Retrieved 2009-04-26.
- ^ "Intel 815 Chipset Family" (PDF). intel.com. Retrieved 2009-05-04.
- ^ "423 Pin Socket (PGA423) Design Guidelines" (PDF). intel.com. Retrieved 2009-05-03.
- ^ "Intel Pentium 4 Processor 478-Pin Socket (mPGA478) Design Guidelines" (PDF). intel.com. Retrieved 2009-05-03.
- ^ "495-Pin and 615-pin micro-PGA ZIF Socket Design Specification Application Note" (PDF). intel.com. Retrieved 2009-05-03.
- ^ "mPGA 604 Socket Mechanical Design Guide" (PDF). intel.com. Retrieved 2009-05-03.
- ^ "mPGA 604 Socket Mechanical Design Guide" (PDF). intel.com. Retrieved 2009-05-03.
- ^ "AMD Sempron Processor Product Data Sheet" (PDF). amd.com. Retrieved 2009-05-03.
- ^ "AMD Opteron Processor Product Data Sheet" (PDF). amd.com. Retrieved 2009-05-03.
- ^ CPU only has 478 pins, but the socket has 479.
- ^ "AMD Opteron Processor Product Data Sheet" (PDF). amd.com. Retrieved 2009-05-03.
- ^ "LGA775 Socket Mechanical Design Guide" (PDF). amd.com. Retrieved 2009-05-04.
- ^ "LGA771 Socket Mechanical Design Guide" (PDF). intel.com. Retrieved 2009-05-03.
- ^ "Low-Profile Socket S1 Design Specification" (PDF). amd.com. Retrieved 2009-05-03.
- ^ "AMD Opteron Processor Product Data Sheet" (PDF). amd.com. Retrieved 2009-05-03.
- ^ "Thermal Design Guide for Socket F (1207) Processors" (PDF). amd.com. Retrieved 2009-05-06.
- ^ "AMD Opteron Processor Product Data Sheet" (PDF). amd.com. Retrieved 2009-05-03.
- ^ CPU only has 938 pins, but the socket has 941.
- ^ "AMD Opteron Processor Product Data Sheet" (PDF). amd.com. Retrieved 2009-05-03.
See also
External links
- Socket ID Guide
- CPU Sockets Chart - A fairly detailed table listing x86 Sockets and associated attributes.
- techPowerUp! CPU Database
- Processor sockets