A differential pair ( 200 ) is provided by routing a printed circuit board ( 202 ) having high density interconnect (HDI) substrate ( 204 ) with first and second metal layers ( 212, 218 ) such that afirst runner ( 206 ) forms a zigzag pattern using the two metal layers while a second runner ( 208 ) forms a second zigzag pattern on the same two metal layers. The first and second zigzag patterns overlap so as to provide orthogonal signal flow.