I have no idea whether it is a 2.5 or 3.5!? All I know is, it is a Lacie/Seagate 350GB HD. It powers up and it seems like it is trying to work, but it never becomes accessible on the computer. I cannot seem to get into the caddy either - have tried to see if there was anything loose, but it seems very well sealed!
Sounds like it wants to engage, but can't! Recovery option sounds expensive too!!!!!