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CPU Sockets Chart

• Socket 7 and Socket 5 are very similar in appearance, but there are significant differences.
  • Socket 7 requires 5.0 amps at 3.3v, while Socket 5 only requires 4.33 amps.
  • The maximum power dissipation for Socket 7 is 17 watts, two watts higher than Socket 5.
  • Vertical clearance above the CPU was raised from 1.35" to 1.75".
  • Socket 7 comes with a 321^st pin located at AH-32 to be used for a KEY pin, which is not electronically connected to either the CPU or the motherboard.
  • Pin AL-01 is changed to Vcc2DET to identify split-rail voltages within newer processors.
  • Socket 7 is defined as a superset of Socket 5, and can handle all the previous processors that worked in Socket 5.
  • Also note that most all Socket 5 motherboards only support 1.5x and 2.0x multipliers, making their maximum processor speed 133MHz (66x2.0). And there are also some Socket 5 boards that can only go up to 120MHz.
• Earlier Socket 7 motherboards do not have split voltage capabilities required by MMX-capable chips (AMD K6, Cyrix 6x86MX, Intel Pentium MMX) as well as the Cyrix 6x86L processor.
• 233MHz (66x3.5) chips utilize the 1.5x multiplier as 3.5x on Socket 7 boards that do not have a jumper for 3.5x. Newer motherboards, on the other hand, will add a third jumper (BF2) to take care of higher clock multipliers.
• Newer chips that use a 4.0x multiplier or higher require a Socket 7 motherboard that has a third multiplier jumper. Unlike using the '1.5x' setting as '3.5x', setting a motherboard to '2.0x' won't produce a '4.0x' multiplier in the chip.
• The 62MHz and 68MHz bus speeds are 'turbo' modes for 60MHz and 66MHz speeds.
• As long as it isn't on-Die, the L2 cache on a Slot 1 processor runs at only half the core processor speed. Slot 2 has processors with full-speed L2 cache and larger size caches (1MB, 2MB).
• All bus speeds listed on this page are actual speeds; not DDR. The Slot A, Socket A, Socket 423/478, Socket 603, and PAC418 chips all use a dual (2x) or quad-pumped (4x) bus that hits on the rising and falling edges of the clock, yielding a faster effective bus speed. The quad-pumped bus works similar to that of AGP 4x mode (it uses a synchronous signal to double strobe each rising and falling edge).
• Socket 775 for the Intel Core 2 chips has a slightly different pinout from Socket T.

Links

Socket Photos
• 486 Socket - 168 pin holes (17x17) PGA LIF socket.
• Socket 1 - 169 pin holes (17x17) PGA LIF socket.
• Socket 2 - 238 pin holes (19x19) PGA ZIF socket.
• Socket 3 - 237 pin holes (19x19) PGA ZIF socket.
• Socket 4 - 273 pin holes (21x21) PGA ZIF socket.
• Socket 5 - 320 pin holes (19x19) SPGA ZIF socket.
• Socket 6 - 235 pin holes (19x19) PGA ZIF socket. Originally intended for low voltage 486DX4 chips, the socket was never released.
• Socket 7 - 321 pin holes (19x19) SPGA ZIF socket.
• Socket 8 - 387 pin holes (24x26) MSPGA ZIF socket.
• Slot 1 - 242 leads. SEC slot.
• Slot 2 - 330 leads. SEC slot.
• Socket 370 - 370 pin holes (19x19) SPGA ZIF socket.
• Socket 418 - 418 pin holes (19x19) SPGA ZIF socket. Originally intended to replace Socket 370 for dual Pentium III chips, the socket was never released.
• Slot A - 242 leads. SEC slot.
• Socket A - 462 (actually 453) pin holes (19x19) SPGA ZIF socket.
• Socket 423 - 423 pin holes (20x20) SPGA ZIF socket.
• Socket 478 - 478 pin holes (26x26) µPGA ZIF socket.
• Socket T - 775 balls (30x33) FC-LGA4 socket.
• Socket 775 - 775 balls (30x33) FC-LGA6 socket.
• Socket 603 - 603 pin holes (31x25) µPGA ZIF socket.
• Socket 604 - 604 pin holes (31x25) µPGA ZIF socket. For faster bus speeds and Low Voltage Xeons.
• PAC418 - 418 pin holes (2x(19x6)) VLIF socket.
• PAC611 - 611 pin holes (25x28) VLIF socket.
• Socket 754 - 754 pin holes (29x29) µPGA ZIF socket.
• Socket 940 - 940 pin holes (31x31) µPGA ZIF socket.
• Socket AM2 - 940 pin holes (31x31) µPGA ZIF socket.
• Various 486 Sockets - Socket 1, 2, 3, and 6.
• Various Pentium Sockets - Socket 4, 5, 7, and 8.