Problems with frames

Hey guys, I've recently upgraded my computer and reinstalled windows after doing so. But, due to an unknown thing I'm sometimes getting some weird frames, especially in games I should have no problems in; Battlefield 3 for example, 1920*1080 high preset sometimes gets under 60 FPS on some DLC maps, which I don't understand.

Also some other games are doing this same thing to me, for example DayZ (I know, not a particualarly good example).

This is my current gear http://teksyndicate.com/users/insanesvk 

I also checked my HDD speeds and my system HDD got ~90 MB/s solid, so I don't think that's an issue there.

Do you guys have any advice whatsoever? Thanks!

Drops like that are very common as long as you're not getting anything like under 30 fps minimum i'd say nothing to worry about. Lots of fires explosions shadows etc will make the frames dip a bit at times. How low is the lowest you have noticed it get too?