Okay so I just bought crysis 3 a couple days ago and decided to start the campaign mode today. When i reached the 'Water Dam' stage, the game looked like it was running on 30FPS even when it showed 65-70 on Mirillis action and dxtory. How is this possible? The game ran very smooth before. I reduced every setting to low but no use.
Even when i play the multiplayer, the game lags terribly for like 5-10 minutes and then runs extremely smooth.

My system Specs:
i7-3770k Processor
8GB DDR3 RAM
1TB HDD
GTX 555

did you oc your gpu?

Also 65-70 fps in singleplayer on a 555gtx while not having everything on low? I really doubt that, the fps shown might be wrong.

I overclocked my gpu, yes. I get 65-70 on high (720p SMAA x2). The gameplay felt really smooth like it should feel when the indicator shows 65-70fps when i played in the fields or on the ship. But the moment i entered that water dam level, the game felt laggy.. And one recording software might be wrong, but how is it possible that both of them show incorrect frames... :/