They aren't using PATA or SATA. They are using ribbon cables to connect boards to each other and to backplate connectors. Some of those ribbon cables could be

They aren't using PATA or SATA. They are using ribbon cables to connect boards to each other and to backplate connectors. Some of those ribbon cables could be carrying serial signaling on some lines but to get it all on one smaller cable with fewer signaling lines like SATA you'd need to mux/demux the data on each end which would add expensive chips to save money on cheap cables.