Oh nice, so at least the server with the 9600 is reaching a good result I would say (best would be C8 to C10) but with some many disks and so many variables that can influence this... it means you have a good result. Regarding the 9500, as you said, your server is quite busy so it is difficult to say if the lower C-states are not reached because of the high demand or because any component of the server could influence this result. I am kinda undecided whether to buy the 9500 or the 9600... both cost a good amount of money and calculating if those boards are more convenient in the long run because they could eventually lead the whole server to lower C-states is a hard problem to think about... My server doesn't go lower than C3 and it consumes 60W-70W at idle while similar builds consume 40ish watts with C8.