I just thought I"d add a comment to be perfectly clear on this subject. A full formatting not affect the physical condition and mechanical functioning of the hard drive but it will erase the hard drive and the drive will need installation of an operating system if it is going to be used as the primary hard drive for a computer system. If it is merely going to be used as a storage device, such as a secondary internal drive or an external drive, then no operating system is needed on it; in other words, the operating system would exist on another drive.