Wipe Hard Drive

From Tyrel's Wiki

So you want to wipe a hard drive to give it away?

Note: This will wipe your ENTIRE HARD DRIVE, so backup any files you wish to save. This will remove your Windows Install.

If you have a CD/DVD burner, the best way is to download DBAN (Darik's Boot and Nuke) and burn it to a CD/DVD.

Here's a link to ImgBurn and DBAN

If you don't have a burner, then you can find an empty flash drive (any size, the file size is like 50mb) (writing an ISO to a flash drive will erase it as well), and write it to that with

Download the program Rufus, and follow the instructions, writing the DBAN.iso file

Either case, when one of those is done, plug/insert it into your computer, and then reboot, press some button to bring up boot menu (Delete/F12/F2, maybe?) and select the new device, then follow instructions within DBAN.