The present invention relates to computer hardware design, and in particular to a printed circuit board (card) comprising wiring dedicated to supply electric board components such as integrated circuits with at least three different reference planes. In particular at locations, where the pins of a card-to-card connector enter the layer structure of the card discontinuities brake the high frequency signal return path of a given signal wiring. In order to close the signal return path around a signal path from card to card including the connector, and thus to limit the signal coupling while concurrently keeping the card design as simple as possible, it is proposed to provide a) an additional capacitance for a given signal wiring in a discontinuity section, b) wherein the additional capacitance is formed by a voltage island placed within a signal layer located next to the given signal wiring.