my iphone5 keeps tripping off while i'm trying to restore and i just bought an unlocked iphone5 which didnt come on after i unsealed the pack

i bought an unlocked iphone5,immediately i unsealed the pack,it was in DFU mode which is quite unusual for a new unlocked phone.i connected it to my itunes account via a laptop and was prompted to restore.problem is when i try to restore,it keeps tripping off before the restore is completed.most of all the error messages i've been getting have to do wit a hardware error.please advise if it can be fixed or i have to get a replacement