many people with good rigs complain about FPS drops during gameplay, even when not in action-intense moments.
I have the same issue and found out that the problem is not the GFX tasking itself, but physX.
[strike]Whenever you have a physX-intense scene going on, the game stutters.[/strike]
Check this post, this guys really goes into the problem. It is possible that crytek had some malfunction programming in terms of physX coding when the cutscenes happen;
http://maldotex.blogspot.com.br/2013/02/performance-bug-in-crysis-3-first-level.html
Eg:
1- whenever psycho shows up big in a cutscene, (a- 1st game cutscene; b- cutscene where he delivers the bow; c- just before the part where you have to go stealth through the grass to find the weapon cache)
2- another one is just after you are delivered the bow and there is a hangar with a lot of waving fabrics over the container boxes, (movement due to the windstorm)
3- another one is when you are going up the water dam elevator and you look towards the valley. FPS goes to the ground.
please developers, either fix this with a driver release or add a feature where we can decrease the quality of physX effects
otherwise, i can set settings to very high with or without AA in 1920, and im OK. (40-60 fps)
my rig:
i7-960 3.2
GTX 485 SLI (4gb VRAM)
12gb RAM DDR 3 tripple channel
500gb hybrid Sata2