From what I can tell, the game is spreading the load of one card between multiple cards (if you're running multi-GPU). At least on my system, none of my cards was utilised more than 33% at it's peak, yet when disabling CFX completely it was working a single GPU to 100% almost the whole time the game was running.
So it's obviously not optimised to spread the workload appropriately (or something). I've never seen this before, but it'd explain why it never seems to hit a limit on either the GPUs or CPU cores.
Consequently, I found that I could get away with pulling back less graphical features to get a (fairly) flat 60fps out of the game by disabling Crossfire in the first place. Still have to pull detail back, just not as much as when running multiple cards.
So it's obviously not optimised to spread the workload appropriately (or something). I've never seen this before, but it'd explain why it never seems to hit a limit on either the GPUs or CPU cores.
Consequently, I found that I could get away with pulling back less graphical features to get a (fairly) flat 60fps out of the game by disabling Crossfire in the first place. Still have to pull detail back, just not as much as when running multiple cards.