Hello all, My iMac is stuck on the grey boot up screen and there is a clicking sound coming from inside the unit. I assume it's the HD failing. One time I got a file with a question mark on the screen but it no longer makes it to that point.Please advise. I'm looking for any help on this, tricks to boot it up and quickly retrieve any of the data off the drive. Or just any way to get the data off. Ugh... : ( I recently backed it up to Time Machine but not sure if that has any value.