Ok I had to download a video codec pack today cause of a movie I wanted to watch, and after the movie i decided to play ACB and noticed a big difference in the video was smother. I installed K-Lite Codec pack for win7 64bit, and Windows 7 Codec Pack v3.0.0, If anyone wants to try to install these and let me know if both game play and cut-scene is smother too then I know it was the codec.
Codec packs are a terrible idea and should never be used by anyone ever.
Just so you know like.
No one needs anything more than FFDShow + MPC.