In this case, someone (not me) somehow managed to totally demolish the mini USB ... fourth pin is actually shoved inward and upward just a bit. Next, cut across the center of the connector.

The 5-pin DIN keyboard connector used with the first IBM PC (1981) and second-generation IBM AT (1984). It was subsequently replaced with the smaller 6-pin Mini-DIN connector on the IBM PS/2 in 1987.