The present invention relates to a method and a printed board assembly for use in a MicroTCA system, wherein backplane pin connectors of the printed board assembly are arranged to be received in receiving connectors of a backplane interconnect, characterized in that it comprises at least one switch unit which is arranged with physical output/input ports that have physical port numbers that can be overridden by logical port numbers, an optimal routing of a number of sets of conductive threads in the printed board assembly arranged so that none of the conductive threads cross over each other while connecting physical output/input ports of the switch units with the backplane pin connectors, and printed circuit board layers arranged to shield signals travelling in the conductive threads in conductive layers of the printed circuit board layers from any significant crosstalk.