Rispondi a "Are the small threaded holes on the logic board serving any function?"I too had the problem, that the thread (tutorial ' Display Assembly ', Step 13, yellow screw) separated from the logic board. Actually I think it was broken off when I opend the phone (crshed display due to droping). You can see this here: position and removed screw and thread: I decided to assemble the phone without this screw and thread. Up to now I did not have any abnormalities (well, I had the iPhone 4 proximity sensor not working after replacing BLACK GSM problem, but I think this is not related). As an electrical engineer I consider it at least as very uncommon to use a shield or antenna as a conductor at the same time. Reasons against are: 1) bad testability of the board while not integrated into handy 2) the use of a screw is not as reliable as a soldered connection. But of course there remains a chance they do it anyhow, as space is really crucial inside such a device! If the shield really has a jumper function at the same time: What kind of malfunction have you found in devices without this screw?