I am looking for a new blank external hard drive, and I found a 2tb bare 3.5 in green hard drive that can be placed in an enclosure, it is 5400 rpm. I also found a 2tb usb 3.0 2.5 in portable hard drive, is there a big difference in performance between these? the portable is smaller, and would be easier to handle, store. The hard drive would be used for storage of photos, videos and documents. is there an advantage of one type over the other, and can one just use portables for storage etc.?