Dna1607-3baa01 i mportant i nformation about the s uper s tack ® ii a dvanced rps p ower m odule (3c16073) and the s uper s tack ® ii 12 port d ual s peed h ub (3c16590) certain 12 port dual speed hub units (3c16590), with the serial number 7yaf017742 or earlier, may not power up automatically from ...