How to completely clear/clean computer memory?

I want to get rid of EVERYTHING on my PC, all downloaded files, pictures, programs. etc.





I want it to go back to the way it was right after I got it out of the box.





Anyways i could do this without the CD? I know there is a CD for it but I lost that,any free ways I could do this?





Thank you.How to completely clear/clean computer memory?
1. You either need the cd, or burn one from the recovery section of your hard drive or in some type of manner, get the operating system onto a cd.





2. Format hard drive.





Tip: both are easy and free, but if you dont know what you are doing, get someone else to do it for you. And if they want to charge you, get someone else to do it. And if THEY want to charge you, see previous sentence.How to completely clear/clean computer memory?
Memory? Turn the computer off. Memory is volatile - what's in it is only there while the power is on.





The ONLY way to revert the HARD DRIVE to the way it was when you got it out of the box is with the CD. You can remove programs and delete files, but you'll probably miss one or two files (at least - probably dozens or hundreds).