Intel's Socket 3, used for 486 processors, was a 19×19 pin grid array socket. However, all compatible processors, to my knowledge, used 17×17 PGA packages. What was the point of the extra pins around the perimeter of the socket? Were they even connected to the motherboard at all?
If the pins are actually used by something, what were their functions? All pinout charts I can find online only show the pins of a 17×17 PGA processor.