What operating system are you using? If you are using a 95/98/ME version, it is a MUST to reformat about every three months to keep your system running optimal. With XP, however, that is different. An XP installation will last indefinately if you take care of it. As for formatting too many times, i've heard of this happening on older hard drives, but haven't heard much about it on newer ones. If I were worried about it, i would do a "quick" format every time because that will erase everything but won't fully format your disk.