HPC-Z interconnections are said to provide signal connections only where desired, with functional isolation for single or double-side surface-mount partitions. Solves thick board drilling and wire density problems. Has capability of isolating high-speed channels on one sub-assembly and low-speed channels on another. Provides interconnections within the board, and reportedly eliminates unnecessary PTH drilling. Vertical connection with a lamination is in place of a PTH; aspect ratios for drill and plate are limited to sub-assembly dimensions. Increased wiring density because of smaller vias and lands.