Alt tab from the game and make sure no processes are taking an unnecessary amount of PC resources. For example, sometimes I will find that xfire, skype, or YIM are taking up a whole cores worth of processing power, which is definitely not what should be happening. Also just make sure most background processes are closed in general as they will just clutter things. If you don't have it already, try
Game Booster which will help close unnecessary back ground processes in bulk.
However, with this new version you will have to manually close the process after running it, since it conflicts with the new anti cheat, Xigncode.