Ive read a few things about these being noisy? I used my MDD dual 867 G4 and its not loud at all? The only time is when I turned it off, then turned it on again, it kinda sounded like a hoover for a few seconds, then fine again... Whats the deal then? Are my fans broken lol, are they supposed to stay on all the time? Or is that noise thing not as bad as people make out?