I am getting a new desk top, and want to donate my old one. It's still in good shape and I've found a suitable charity. I would like to know the safest way to delete EVERYTHING of the hard drive before I get rid of it. I'm most concerned about passwords, numbers and financial info. Thanks for any help you can give me.
The best way that I know of is to obtain wipe secure software that will over write every sector and partition with 0's & 1's. I would reformat the drive, reinstall Window before wiping the drive clean. Some of this software is free, others you have to pay for. It is recommended that you get software that will overwrite your drive several times. I've seen recommendations of over writing at least three times, and I've seen other articles that say do it at least seven times. I have used wipe secure software in the past, and just one over write will take about one day.
Here are a couple of articles.
http://www.pcworld.com/article/id,110338-page,1/article.html
http://www.microsoft.com/athome/moredone/protectpurgepersonalfiles.mspx
This software looks like decent freeware.
http://www.softpedia.com/get/Security/Security-Related/DP-WIPER.shtml
BC Wipe is quite widely used. DoD and Gutmann wipe routines. I wouldn't donate without at least using something or removing the drive and use the most secure wipe routine, 10# sledge. Even the FBI are hard pressed to get data forensics off small platter pieces.
Link for BC wipe for comparison.
http://www.jetico.com/index.htm#/bcwipe_faq.htm