This is a 4 layer PCB with double sided edge connectors at the front and rear. The top is populated with DIP integrated circuits and a variety of discrete components. The left card extractor has "XYD" stamped on it. This board is the XY Driver for a core memory board in an HP2100 minicomputer.
Hewlett-Packard Company (HP)
Written in white ink near front edge on top of board