had problem with my ST3500340AS also, send to a data recovery centre n they said the damage platter caused the firmware to corrupt, but they said can 99.9% recovery, since the platter is damage how can? saw this forum, seems buying same ST3500340AS can replace the PCB n it will ok? what about the firmware? this hard disk never banged etc, only sleep mode n after that cannot detect, 1st was able to see in USB as mass storage ok, then device manager ok, then disk drive ok, but without drive letter...now only can have in USB mass storage ok, provided i plug to enclosure box, if not, the PC stuck also. any friend plz advise can i get a ST3500340AS regardless of firmware n send to a technical etc? thank you