<hardware, standard> One of the series of standard sockets into which you can plug various x86 microprocessors. These vary in the number of pins, package, voltages, bus speeds, and supported processors. Motherboards often have clock multipliers so that the processor runs at a multiple of the bus speed. Socket 1, 169 pin LIF/ZIF PGA (17x17), 5v, 16-33 MHz 486 SX, 486 DX, 486 DX2, DX4 Overdrive. Socket 1 was the first standard Intel 486 socket. Socket 2, 238 pin LIF/ZIF PGA (19x19), 5v, 25-50 MHz 486 SX, 486 DX, 486 DX2, 486 DX4, DX4 & Pentium Overdrive. Updated Socket 1, added support for Pentium Overdrive processors. Socket 3, 237 pin LIF/ZIF PGA (19x19), 3.3/5v, 25-50 MHz 486 SX, 486 DX, 486 DX2, 486 DX4, DX4 & Pentium Overdrive. Supports 5V & 3.3V processors, considered the latest 486 socket. Socket 4, 273 pin LIF/ZIF PGA (21x21), 5v, 60/66 MHz Pentium 60/66 and Pentium Overdrive, only 5v. Socket 5, 296 pin LIF/ZIF, 320 pin LIF/ZIF SPGA (19x19 or 37x37), 3.3v, 50/60/66 MHz Pentium 75 - 133MHz, Pentium Overdrive, only 3.3v. Socket 6, 235 pin ZIF PGA (19x19), 3.3v, 25-40MHz. Unpopular advanced Socket 3, rarely seen / paper spec 486 DX4, Pentium Overdrive, only 3.3v. See also Socket 7, Socket 8, Super 7, Slot 1, {Slot 2}, Slot A. {CPU Sockets chart (http://users.erols.com/chare/sockets.htm)}. CPU Sockets (http://webm3308.ntx.net/cpusockets.htm). (1999-08-05)

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.

and so cannot be subject to patent claims. The pre-586 subset of the x86 architecture is therefore fully open.