Just replaced my 36Gb Raptor and 80Gb Seagate 'cuda IV with a WD 3200KS (320Gb, 16mb cache, SATAII). It is in my Antec Sonata II and is so mounted on the rubber grommets on the HDD trays but it still makes a loud hum when powered up which is causing bad vibrations, so much so i can hear it in bed (very slightly) upstairs! Even both the Raptor and Seagate in the case at the same time were quieter. What do u think my chances of a refund from O/C are as i cant put up with this, delivered last Friday? I knew i should of got the 250Gb Samsung P120S. (i've remounted it on a different tray and everything, still not good).