The VX4380 256-Crosspoint Relay Matrix Module is a printed circuit board assembly for use in a mainframe conforming to the VXIbus Specification. The VX4380 provides four 4 16 2-wire matrix sections. Each section can be configured to connect either the four rows or the sixteen columns to the section above or below it to produce up to a 16 16 2-wire matrix or a 4 64 2-wire matrix.