Fps drop/stutters

Ill start off by saying that my computer is pretty nuts, just to close that out. I can run every game on Max graphics and not have any fps issues, but for some reason ever since Bwl came out im having fps drops/stutters every raid (especially on razorgore and the techinicans. And last week i Even started getting it in mc. (I never Get any fps drop at all outside of raids). I have fps capped at 100 and it will often go down to 70 for a second then back up to 100 in mc and bwl. I never had any issues in mc before bwl btw. Any ideas what could be causing it?