Blissz from what I am seeing I can put each miner on autotune and allow it to determine which card can take more.  I already know all my rigs are good at minimum 450 and 7 or 8.  Mostly 456.   Once it goes thru the process I can then go back in and adjust each card to either the new higher frequency or revert back to the old stable settings.   On the first try the autotune actually took one of my cards and lowered it way lower than was actually stable so I went back in after it was finished and changed it back to the higher setting.   Make sense?