How can I tell if I have a 4X or 8X superdrive? I bought a rev A 2.5 G5 with the liquid cooling (rev A? - ordered day they were announced). I thought they were 4X drives and at some magic point were secretly upgraded? But I was wondering how I could tell - I remember some rumor all G5s had 4X but they were really locked down 8X or some silly non sense.... or not.... Any simple answers?