If you’re still using Windows 7, you can boot up your computer using DBAN (also known as Darik’s Boot and Nuke) and use it to wipe an internal drive. Windows 7 doesn’t contain any integrated disk-wiping features. Windows 7 (and Computers Without Operating Systems) In theory, you should only need a single pass, but you might want to perform a few extra to be safe. Doing this to solid-state storage can decrease the life of your drive, so try not to use more passes than you really need. You could enter “/p:3” to perform three passes, and so on. For example, “/p:1” will perform a single pass on the drive, overwriting every sector once.
The “/p” switch tells Windows how many passes to use. Replace “x:” with the drive letter of the drive you want to format, being very careful to select the correct drive or you’ll wipe another drive. To do this, launch a Command Prompt window as administrator by right-clicking the Start button and selecting “Command Prompt (Admin).” Type the following command into the window:
