It's not memory you are deleting, as that disappears every time you turn the computer off.
It is the data on the hard drive you are talking about.
Best way, DBAN it, (Darik's Boot and Nuke) utility;
http://www.dban.org/
That wipes everything off the hard drives. Nothing is left.
Mark
how do you wipe clean a windows xp pc to safely recycle it? i want to erase everything. can i do it manually or is there software to download? thank you for your help.

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