So I recently purchased C&C3 off Origin and decided to have a bash on the campaign, however I've been having terrible issues with slow and choppy game play, everything just seems to be lagging no matter what resolution/settings I choose be it Medium or High etc.. I also noticed on the end mission screen that the game was claiming it had only taken me 11 minutes to complete the missions, when in real time it had taken me much longer.
I don't know if its linked but I also noticed that the Main Menu and Boot screens also seem to be choppy.

My system specs are:

Intel Core i5 2500k 3.30GHz
HD6870
8GB RAM

Windows 7 Home Premium 64bit