CPU socket

From Wikipedia, the free encyclopedia
LGA 775, a land grid array socket
Socket AM2+, a pin grid array socket

In computer hardware, a CPU socket or CPU slot contains one or more mechanical components providing mechanical and electrical connections between a microprocessor and a printed circuit board (PCB). This allows for placing and replacing the central processing unit (CPU) without soldering.

Common sockets have retention clips that apply a constant force, which must be overcome when a device is inserted. For chips with many pins, zero insertion force (ZIF) sockets are preferred. Common sockets include Pin Grid Array (PGA) or Land Grid Array (LGA). These designs apply a compression force once either a handle (PGA type) or a surface plate (LGA type) is put into place. This provides superior mechanical retention while avoiding the risk of bending pins when inserting the chip into the socket. Certain devices use Ball Grid Array (BGA) sockets, although these require soldering and are generally not considered user replaceable.

CPU sockets are used on the motherboard in desktop and server computers. Because they allow easy swapping of components, they are also used for prototyping new circuits. Laptops typically use surface-mount CPUs, which take up less space on the motherboard than a socketed part.

As the pin density increases in modern sockets, increasing demands are placed on the printed circuit board fabrication technique, which permits the large number of signals to be successfully routed to nearby components. Likewise, within the chip carrier, the wire bonding technology also becomes more demanding with increasing pin counts and pin densities. Each socket technology will have specific reflow soldering requirements. As CPU and memory frequencies increase, above 30 MHz or thereabouts, electrical signalling increasingly shifts to differential signaling over parallel buses, bringing a new set of signal integrity challenges. The evolution of the CPU socket amounts to a coevolution of all these technologies in tandem.

Modern CPU sockets are almost always designed in conjunction with a heat sink mounting system, or in lower power devices, other thermal considerations.

Function[edit]

A CPU socket is made of plastic, and often comes with a lever or latch, and with metal contacts for each of the pins or lands on the CPU. Many packages are keyed to ensure the proper insertion of the CPU. CPUs with a PGA (pin grid array) package are inserted into the socket and, if included, the latch is closed. CPUs with an LGA (land grid array) package are inserted into the socket, the latch plate is flipped into position atop the CPU, and the lever is lowered and locked into place, pressing the CPU's contacts firmly against the socket's lands and ensuring a good connection, as well as increased mechanical stability.

List[edit]

80x86[edit]

Table legend:

  Intel only
  AMD only
Socket
name
Year of introduction CPU families supported Computer type Package Pin count Pin pitch
(mm)
Bus clock &
transfers
Notes
DIP 1970s Intel 8086
Intel 8088
DIP 40 2.54 5/10 MHz
PLCC ? Intel 80186
Intel 80286
Intel 80386
PLCC 68 to 132 1.27 6–40 MHz
PGA 168 ? Intel 80486
AMD 486
Cyrix 486
PGA 168 2.54 16–50 MHz Sometimes referred to as Socket 0 or Socket 486
Socket 1 1989 Intel 80486
AMD 486
AMD 5x86
Cyrix 486
Cyrix 5x86
PGA 169 2.54 16–50 MHz
Socket 2 ? Intel 80486
Intel Pentium Overdrive (P24T)
Intel DX4
AMD 486
AMD 5x86
Cyrix 486
Cyrix 5x86
PGA 238 2.54 16–50 MHz
Socket 3 1991 Intel 80486
Intel Pentium Overrdrive (P24T)
Intel DX4
AMD 486
AMD 5x86
Cyrix 486
Cyrix 5x86
IBM Blue Lightning
PGA 237 2.54  16–50 MHz[a]
Socket 4 1993 Intel Pentium PGA 273 ? 60–100 MHz
Socket 5 1994 Intel Pentium
AMD K5
Cyrix 6x86
IDT WinChip C6
IDT WinChip 2
PGA 320 ? 50–100 MHz
Socket 6 ? Intel 80486 PGA 235 ? ? Designed but not used
Socket 463/
Socket NexGen
1994 NexGen Nx586 PGA 463 ? 37.5–66 MHz
Socket 7 1994 Intel Pentium
Intel Pentium MMX
AMD K6
PGA 321 ? 50–66 MHz It is possible to use Socket 7 processors in a Socket 5. An adapter is required, or if one is careful, a socket 7 can be pulled off its pins and put onto a socket 5 board, allowing the use of socket 7 processors.
Socket 8 1995 Intel Pentium Pro PGA 387 ? 60–66 MHz
Slot 1 1997 Intel Pentium II
Intel Pentium III
Desktop Slot 242 ? 66–133 MHz Celeron (Covington, Mendocino)
Pentium II (Klamath, Deschutes)
Pentium III (Katmai)- all versions
Pentium III (coppermine)
Super Socket 7 1998 AMD K6-2
AMD K6-III
Rise mP6
Cyrix MII
PGA 321 ? 66–100 MHz Backward compatible with Socket 5 and Socket 7 processors.
Slot 2 1998 Intel Pentium II Xeon
Intel Pentium III Xeon
Server Slot 330 ? 100–133 MHz
Socket 615 1999 Intel Mobile Pentium II
Intel Mobile Celeron
Notebook PGA 615 ? 66 MHz
Slot A 1999 AMD Athlon Desktop Slot 242 ? 100 MHz
Socket 370 1999 Intel Pentium III
Intel Celeron
VIA Cyrix III
VIA C3
Desktop PGA 370 1.27[1] 66–133 MHz
Socket A/
Socket 462
2000 AMD Athlon
AMD Duron
AMD Athlon XP
AMD Athlon XP-M
AMD Athlon MP
AMD Sempron
Desktop PGA 462 ? 100–200 MHz
400 MT/s[b]
Socket 423 2000 Intel Pentium 4 Desktop PGA 423 1[2] 100 MHz
400 MT/s
Willamette core only.
Can accept some of Socket 478 CPU with an adapter
Socket 495 2000 Intel Celeron
Intel Pentium III
Notebook PGA 495 1.27[3] 66–133 MHz
Socket 603 2001 Intel Xeon Server PGA 603 1.27[4] 100–133 MHz
400–533 MT/s
Socket 478/
Socket N
2001 Intel Pentium 4
Intel Celeron
Intel Pentium 4 EE
Intel Pentium 4 M
Desktop PGA 478 1.27[5] 100–200 MHz
400–800 MT/s
Socket 563 2002 AMD Athlon XP-M Notebook PGA 563 ? 333 MHz
Socket 604 2002 Intel Xeon Server PGA 604 1.27[4] 100–266 MHz
400–1066 MT/s
Socket 754 2003 AMD Athlon 64
AMD Sempron
AMD Turion 64
Desktop PGA 754 1.27[6] 200–800 MHz
Socket 940 2003 AMD Opteron
AMD Athlon 64 FX
Desktop
Server
PGA 940 1.27[7] 200–1000 MHz
Socket 479 2003 Intel Pentium M
Intel Celeron M
Notebook PGA 479[8] ? 100–133 MHz
400–533 MT/s
Socket 939 2004 AMD Athlon 64
AMD Athlon 64 FX
AMD Athlon 64 X2
AMD Opteron
Desktop PGA 939 1.27[9] 200–1000 MHz 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
Desktop LGA 775 1.09 x 1.17[10] 1600 MHz Can accept LGA 771 CPU with slight modification and use of an adapter
Socket M 2006 Intel Core Solo
Intel Core Duo
Intel Dual-Core Xeon
Intel Core 2 Duo
Notebook PGA 478 ? 133–166 MHz
533–667 MT/s
Replaces Socket 479
LGA 771/
Socket J
2006 Intel Xeon Server LGA 771 1.09 x 1.17[11] 1600 MHz See LGA 775/Socket T above
Socket S1 2006 AMD Turion 64 X2 Notebook PGA 638 1.27[12] 200–800 MHz
Socket AM2 2006 AMD Athlon 64
AMD Athlon 64 X2
Desktop PGA 940 1.27[9] 200–1000 MHz Replaces Socket 754 and Socket 939
Socket F/
Socket L (Socket 1207FX)
2006 AMD Athlon 64 FX
AMD Opteron
(Socket L only support Athlon 64 FX)
Desktop
Server
LGA 1207 1.1[13] Socket L: 1000 MHz in Single CPU mode,
2000 MHz in Dual CPU mode
Replaces Socket 940
Socket L was intended for enthusiasts who wanted server power in a desktop PC. It is just a re-branded Socket F that doesn't need special RAM, and may have only been used in the Asus L1N64-SLI WS Motherboard.
Socket AM2+ 2007 AMD Athlon 64
AMD Athlon X2
AMD Phenom
AMD Phenom II
Desktop PGA 940 1.27[9] 200–2600 MHz Separated power planes
Replaces Socket AM2
AM2+ Pkg. CPUs can work in Socket AM2
AM2 Pkg. CPUs can work in Socket AM2+
Socket P 2007 Intel Core 2 Notebook PGA 478 ? 133–266 MHz
533–1066 MT/s
Replaces Socket M
LGA 1366/
Socket B
2008 Intel Core i7 (900 series)
Intel Xeon (35xx, 36xx, 55xx, 56xx series)
Desktop
Server
LGA 1366 ? 4.8–6.4 GT/s Replaces Socket J (LGA 771) in the entry level.
Socket AM3 2009 AMD Phenom II
AMD Athlon II
AMD Sempron
AMD Opteron (1300 series)
Desktop PGA 941[14] or 940[15] 1.27[9] 200–3200 MHz Separated power planes
Replaces Socket AM2+
AM3 Pkg. CPUs can work in Socket AM2/AM2+
Sempron 140 only
rPGA 988A/
Socket G1
2009 Intel Clarksfield
Intel Arrandale
Notebook rPGA 988 1 2.5 GT/s Replaces Socket P
LGA 1156/
Socket H
2009 Intel Nehalem (1st gen)
Intel Westmere
Desktop LGA 1156 ? 2.5 GT/s DMI bus is a (perhaps modified) PCIe x4 v1.1 interface
Socket G34 2010 AMD Opteron (6000 series) Server LGA 1974 ? 200–3200 MHz Replaces Socket F
Socket C32 2010 AMD Opteron (4000 series) Server LGA 1207 ? 200–3200 MHz Replaces Socket F, Socket AM3
LGA 1567/
Socket LS
2010 Intel Xeon 6500/7500-series Server LGA 1567 ? 4.8–6.4 GT/s
LGA 1155/
Socket H2
2011/Q1
2011.01.09
Intel Sandy Bridge (2nd gen)
Intel Ivy Bridge (3rd gen)
Desktop LGA 1155 ? 5.7 GT/s used for Intel 2nd generation, 3rd generation processors.


Sandy Bridge supports 20 PCIe 2.0 lanes.
Ivy Bridge supports 40 PCIe 3.0 lanes.
Intel Mainstream Socket.

LGA 2011/
Socket R
2011/Q3
2011.11.14
Intel Core i7 3xxx Sandy Bridge-E
Intel Core i7 4xxx Ivy Bridge-E
Intel Xeon E5 2xxx/4xxx (Sandy Bridge EP) (2/4S)
Intel Xeon E5-2xxx/4xxx v2 (Ivy Bridge EP) (2/4S)
Desktop
Server
LGA 2011 ? 4.8–6.4 GT/s Sandy Bridge-E/EP and Ivy Bridge-E/EP both support 40 PCIe 3.0 lanes.
Using the Xeon focused 2011 socket gives also 4 memory Channels.
rPGA 988B/
Socket G2
2011 Intel Core i7
Intel Core i5
Intel Core i3
(2000, 3000 series)
Notebook rPGA 988 1 2.5 GT/s, 4.8 GT/s
Socket FM1 2011 AMD Llano Processors Desktop PGA 905 1.27 5.2 GT/s used for 1st generation APUs
Socket FS1 2011 AMD Llano Processors Notebook PGA 722 1.27 3.2 GT/s used for 1st generation Mobile APUs
Socket AM3+ 2011 AMD FX Vishera
AMD FX Zambezi
AMD Phenom II
AMD Athlon II
AMD Sempron
Desktop PGA 942 (CPU 71pin) 1.27 3.2 GT/s
LGA 1356/
Socket B2
2012 Intel Xeon (E5 1400 & 2400 series) Server LGA 1356 ? 3.2–4.0 GT/s
Socket FM2 2012 AMD Trinity Processors Desktop PGA 904 1.27 ? used for 2nd generation APUs
LGA 1150/
Socket H3
2013 Intel Haswell (4th gen)
Intel Haswell Refresh
Intel Broadwell (5th gen)
Desktop LGA 1150 ? ? used for Intel's 4th generation (Haswell/Haswell Refresh), the handful of intel 5th generation processors
rPGA 946B/947/
Socket G3
2013 Intel Haswell Notebook rPGA 946 1 5.0 GT/s
Socket FM2+ 2014 AMD Kaveri
AMD Godavari
Desktop PGA 906 1.27 ? Compatible with AMD APUs such as "Richland" and "Trinity"
Socket AM1 2014 AMD Athlon
AMD Sempron
Desktop PGA 721 1.27 ? Compatible with AMD APUs such as "Kabini"
LGA 2011-v3 2014
(August and September)
Haswell-E
Haswell-EP
Desktop LGA 2011 ? Up to 68 GB/sec.
Depends on DDR4 speed and channel count.
Up to 40 PCIe 3.0 lanes.
Up to 4 memory Channels.
LGA 1151/
Socket H4
2015 Intel Skylake (6th gen)
Intel Kaby Lake (7th gen)
Intel Coffee Lake (8th gen)
Intel Coffee Lake Refresh (9th gen)
Desktop LGA 1151 ? 5 GT/s - 8 GT/s used for Intel's 6th generation (Skylake), 7th generation (Kaby Lake), 8th generation (Coffee Lake) processors, and 9th generation (Coffee Lake Refresh) processors
LGA 3647 2016 Intel Xeon Phi
Intel Skylake-SP
Server LGA 3647 ? ? used for Intel's Xeon Phi x200 and Xeon Scalable processors
Socket AM4 2016

AMD Athlon Bristol Ridge
AMD Athlon Raven Ridge 14nm
AMD Athlon Picasso 12nm
AMD Ryzen 1000 series
AMD Ryzen 2000 series
AMD Ryzen 3000 series
AMD Ryzen 4000 series
AMD Ryzen 5000 series

Desktop PGA 1331 1 Depends on DDR4 speed compatible with AMD Ryzen 9, Ryzen 7, Ryzen 5 & Ryzen 3 Zen based processors
Socket SP3 2017 AMD Epyc Naples
AMD Epyc Rome
AMD Epyc Milan
Server LGA 4094 ? Depends on DDR4 speed compatible with AMD Epyc processors
Socket TR4/
Socket SP3r2
2017 AMD Ryzen Threadripper (1000 series)
AMD Ryzen Threadripper (2000 series)
Desktop LGA 4094 ? Depends on DDR4 speed compatible with AMD Ryzen Threadripper processors
LGA 2066/
Socket R4
2017 Intel Skylake-X
Intel Kaby Lake-X
Intel Cascade Lake-X
Desktop
Server
LGA 2066 ? ? Used for Intel's 7th generation (Skylake-X & Kaby Lake-X & Cascade Lake-X) series of Core-X processors
Socket sTRX4/
Socket SP3r3
2019 AMD Ryzen Threadripper (3000 series) Desktop LGA 4094 ? Depends on DDR4 speed compatible with 3rd generation AMD Ryzen Threadripper processors
LGA 4189 2020 Intel Cooper Lake
Intel Ice Lake-SP
Desktop
Server
LGA 4189[16] 0.99[16]
LGA 1200 2020 Intel Comet Lake (10th gen)
Intel Rocket Lake (11th gen)
Desktop LGA 1200
LGA 1700 2021 Intel Alder Lake (12th gen)
Intel Raptor Lake (13th gen)

Intel Raptor Lake (14th gen)

Desktop LGA 1700
Socket sWRX8 2022 AMD Ryzen Threadripper Pro (5000 series) Desktop LGA 4094
Socket AM5 2022 AMD Ryzen 7000 series
AMD Ryzen 8000 series (APU)
Desktop LGA 1718 Zen 4 Ryzen CPUs
Socket SP5 2022 AMD Epyc Genoa Server LGA 6096 Used for Epyc Genoa and Milan
LGA 4677 2022 Intel Sapphire Rapids Server LGA 4677
Socket SP6 2023 AMD Epyc Siena Server LGA 4844
Socket sTR5 2023 AMD Ryzen Threadripper
AMD Ryzen Threadripper Pro (7000 series)
Desktop LGA 4844
LGA 7529 2024 Intel Sierra Forest Server LGA 7529
Socket
name
Year of introduction CPU families supported Computer type Package Pin count Pin pitch
(mm)
Bus clock &
transfers
Notes
  1. ^ Some late model Socket 3 motherboards unofficially supported FSB speeds up to 66MHz
  2. ^ This is a double data rate bus. FSB in the later models.

Other ISAs[edit]

Socket
name
Year of introduction CPU families supported Computer type Package Pin count Pin pitch
(mm)
Bus clock &
transfers
Notes
Daughter Card 1995 PowerPC 601+ Desktop Slot 146 ? 40-60 Hz
Socket 288 ? PowerPC 603+ Desktop PGA 288 ? 40-60 Hz
Socket 431 1995 Alpha 21064/21064A Desktop PGA 431 ? 12.5–66.67 MHz
Socket 499 1997 Alpha 21164/21164A Desktop PGA 499 ? 15–100 MHz
Socket 587 1998 Alpha 21264 Desktop PGA 587 ? 12.5–133 MHz
Slot B 1999 Alpha 21264/21264A Desktop Slot 587 ? 100 MHz[17]
PAC418 2001 Intel Itanium Server PGA 418 ? 133 MHz
PAC611 2002 Intel Itanium 2
HP PA-8800, PA-8900
Server PGA 611 ? 200 MHz
LGA 1248 2010 Intel Itanium 9300-series and up Server LGA 1248 ? 4.8-6.4 GT/s
Socket
name
Year of introduction CPU families supported Computer type Package Pin count Pin pitch
(mm)
Bus clock &
transfers
Notes

Slotkets[edit]

Slotkets are special adapters for using socket processors in bus-compatible slot motherboards.

See also[edit]

References[edit]

  1. ^ "Intel 815 Chipset Family" (PDF). Intel. Retrieved May 4, 2009.
  2. ^ "423 Pin Socket (PGA423) Design Guidelines" (PDF). Intel. Archived (PDF) from the original on December 29, 2009. Retrieved May 3, 2009.
  3. ^ "495-Pin and 615-pin micro-PGA ZIF Socket Design Specification Application Note" (PDF). Intel. Retrieved May 3, 2009.
  4. ^ a b "mPGA 604 Socket Mechanical Design Guide" (PDF). Intel. Retrieved May 3, 2009.
  5. ^ "Intel Pentium 4 Processor 478-Pin Socket (mPGA478) Design Guidelines" (PDF). Intel. Retrieved May 3, 2009.
  6. ^ "AMD Sempron Processor Product Data Sheet" (PDF). AMD. Retrieved May 3, 2009.
  7. ^ "AMD Opteron Processor Product Data Sheet" (PDF). AMD. Retrieved May 3, 2009.
  8. ^ CPU only has 478 pins, but the socket has 479.
  9. ^ a b c d "AMD Opteron Processor Product Data Sheet" (PDF). AMD. Retrieved May 3, 2009.
  10. ^ "LGA 775 Socket Mechanical Design Guide" (PDF). Intel. Retrieved May 4, 2009.
  11. ^ "LGA771 Socket Mechanical Design Guide" (PDF). Intel. Retrieved May 3, 2009.
  12. ^ "Low-Profile Socket S1 Design Specification" (PDF). AMD. Retrieved May 3, 2009.
  13. ^ "Thermal Design Guide for Socket F (1207) Processors" (PDF). AMD. Retrieved May 6, 2009.
  14. ^ CPU only has 938 pins, but the socket has 941.
  15. ^ AMD Documentation "Socket AM3 design Specification" (PDF). AMD. Retrieved January 5, 2012.
  16. ^ a b "LGA 4189 Socket and Hardware" (PDF).
  17. ^ Hachman, Mark (February 2, 1999). "Alpha camp moves to "Slot B" connector to push further into workstations". EE Times. Retrieved November 10, 2022.

External links[edit]