Does anyone know an application that does ZERO OUT of any HD.
And is must be free, not an trial

http://dban.sourceforge.net/

bob.

Seagate Seatools also zero fills drives, & not just Seagate drives but
every drive you use it on, it even shows you jumper settings for all drives
whilst booted to it in dos...

Killdisk does as well, although the versions you'll find on the internet
will be trial versions, they don't expire, but only work on the floppy
or the Master IDE...

dd if=/dev/zero of=/dev/hda

If you have access to a Linux or *NIX box, you can use RentedMule's approach (remember you have to substitute the device name with the appropriate one). But you can also do it from within Windows XP or newer. Fire up diskpart (CLI-based), select the disk you want to zero out, and then do