Dell has determined that my NTSB hard drive on my Studio 1555 is faulty, so they have sent me a new hard drive and want the old one sent back to them. I don't intend to send them my old drive without first cleaning the disk of personal information, but when I used Darik's Boot and Nuke, the program reported bad sectors on the hard drive and aborted the HD wipe after only four seconds into the process. Dell won't allow me to physically damage the HD before sending it back, so is there another way I can render it unreadable without doing damage?

I have heard that a magnet will wipe it, but I don't know how that works. The strongest magnet I have is probably a ten or fifteen pound one from an audio speaker.

Any help you can give? I'm on an extremely tight deadline to get this done, unfortunately.

Thanks.