I noticed an interesting thing about the power stats outputted from the "nvidia-smi -q" command for each physical GPU. If you double the Max Power Limit (as there are two GPUs per board) that equals above the published maximums for the board. For instance the K2 would be 125W x 2 = 250 W and the M60 would be 162W x 2 = 324W. You can see those are above the published maximums below for the K2 and M60 cards.
K2: 225 W
M60: 300 W
Perhaps this per-GPU maximum power draw allows the single GPU to enter it’s “boost” mode temporarily. And, that would only occur in the case that the other physical GPU on the board is far enough below its maximum power draw not to exceed the published limit for the entire board. Is this the case?