I've tried the Seatools a number of times now and it's failed each time. So it's looking like it is the drive, but thank you to everyone who made other suggestions, as it's one of those faults that can be hard to track down.
I was reading on another forum someone had 12 Seagate drives die in 3 months, and the Seagate forums are full of irate drive owners. I'll RMA the drive again (after using eraser on it) and ask for a different make (not Maxtor as they're now owned by Seagate too)
Thanks again folks
