Ok i have discovered what setting causes FPS drops, i can change every settings from lowest to highest and there is no change apart from OBJECT DETAIL (this was the same with arma 2, but anything below high looked awful, same with arma 3 sadly)

If i set it to below high, my fps never drops below 30 (this is with everything absolutely maxed)

Anything over standard and this issue happens, they have to optimize this setting this time round, its not fair to have on graphics setting that has to run low making everything look shit, when i can max all others.

Exact same issue, what ever settings i have it on, lowest to highest - 25-50 frames, if i look at a bunch of trees it will drop massively.
Specs:
Windows 7
Intel I7 3.2ghz
AMD GPU 6970 2gb
Looks like the game only uses one bloody cpu core.....