Hi everyone. So a long time ago I bought a pc from a friend. I just barely started learning about pc's and when I opened it up 2 weeks ago I saw that it had 2 HDD's, a 500GB and a 1TB. The 1TB wasn't even connected it was just sitting there. Well that computer doesnt work anymore so Icant use it. I just pulled out the 1TB HDD and plugged it in a very old sony viao. I went to control panel, switched to classic view, administrative tools, computer management, and disk management. Under Disk 0 is an HDD with a cut in the middle which says EISA. I believe this is windows xp that came for free with the sony vaio computer. Disk 1 has 931.51 healthy space. I believe this indicates the 1TB HDD works. Now what? How can I check if its completely 100% clean (free of absolutely any data)? Should I use dban on it. Also now that it's hooked up in the old computer is it part of the LocalDisk(C: )? Will stuff start getting saved on it?