Better to use #DBAN to wipe a drive: http://www.dban.org/ And on modern drives multiple passes don't really help to remove data http://www.securityfocus.com/brief/888 On the other hand, Peter Gutmann says " By deliberately under-stating the requirements for media sanitization in publicly-available guides, intelligence agencies can preserve their information-gathering capabilities while at the same time protecting their own data using classified techniques." http://www.cs.auckland.ac.nz/~pgut001/pubs/secure_del.html !infosec !surveillance