Intel computer processor socket that had 237-pin holes in 19 by 19 rows, ran at 3.3v and 5v, and was compatible with the Intel 486SX, 486DX, 486DX2, 486DX4, and OverDrive processors. To the right, is an illustration of what this socket looks like. Unlike the Socket 2 processor, the Socket 3 processor has additional pins in the bottom-left portion of the socket to help provide better keying and prevent the processor from being installed improperly.
Note: This socket is not compatible with 3v processors and often was found on motherboards that had a coprocessor socket. Also, this socket cannot determine the voltage provided and must rely on a jumper that allows you to select either 3.3v or 5v.