I usually run EVGA Precision to monitor my 670s (two) when I'm playing and I literally just noticed during a scene when it dropped to 20 fps for an extended period of time - my GPU usages were at like 50% each.

So, it clearly is a problem with the SLI profile that NVIDIA has. Has anyone heard/found a fix for the problem yet?

Did u update to the latest drivers from Nvidia that came out last night? That fixed up the SLI profiles, 65% increase on SLI.

The 314 WHQL? Yes of course before I even started playing the game. They do nothing.

I was having problems with evga precision. try using msi afterburner to see if its just a monitoring glitch. If thats not it, try re-installing the drivers, and do a clean install, then make sure to reboot your pc. sli working great on my 690, 95-100% on both cards.

it clearly is a problem with the SLI.
This behaviour also happens with a single GPU, i have noticed this happen in Crysis2 with a GTX 580 (99% down to 30%). Although it isn't an extended reduced percentage drop, it happens none the less in different levels in certain areas.