Hmm, 2nd harddrive shouldnt be a problem unless its a desktop case, then you might not have enough room for one. Id recommend buying a new one, or a used one thats a little bit bigger. The PB's Mobo shouldnt have a problem with a 2nd harddrive, just make sure your IDE cable has a place for another harddrive. As for the ram, Im not totally sure about that. Depends on the CPU/board.