Cleaning up my office at home and have some old PCs to get rid of. Usually I fire up DBAN live CD to wipe any hard disks before disposal. Unfortunately, one of my PCs refuses to run DBAN properly. Don't want to spend a bunch of time on this so I Googled and found this article.
Fire up a Knoppix Live CD, open a terminal and run the following:
# shred -n 5 -vz /dev/sda
-n 5: Overwrite 5 times instead of the default (25 times)
-v : Show progress
-z : Add a final overwrite with zeros to hide shredding
Thanks. Works great.