Fake?
Looking at the top of the touch screen, that grille pattern is what all the knock-off white iPhone 4 parts used to cover the proximity sensor (mine certainly does). If you look at an official white iPhone 4 it has a dark lozenge in that position.
So unless Apple have decided to imitate the cheap copies I would seriously wonder if someone just decided to take some pictures of their iPhone 4 in pieces and photoshop the letters A5 over the CPU...