Well, no, what would be the reason for formating the HDD? if it has the OS you want on it then just leave it as it may cuase problems to the HDD if the format is not needed. Also, when buying the HDD, did it come with things on it? or is is brand new? If it came with things on it, then take a look at whats on it and if it seems wierd or fishey, then format it. But unccessasary formats could cuase damage in the long run

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What is a physical body. The body is merely an object. It is a form of existence far too impure to store the gods within us called souls. Now you will remember. The bloodstained history. Material desire. Hunger. Sexual Drive. Desire to dominate. Desire for fame. Humanity. As long as there is a body, desires will be born. The human ego will never disappear as long as desire remains present. Humans will continue to fight to fulfill their bodies desires and it will never end. At this rate there is no future.