Assassin's creed fps issue

I have been having an issue with my new 7950 and assassin's creed 3. While outside I usually get between 22 and 34 fps, and my gpu is only at about 20-40% usage. So that leads me to believe that I should be getting 40-60fps. So my question is why wouldn't it be getting higher fps? And how can I solve it? Also, in cut scenes it gets higher fps and I get 70%+ usage at these points. It's only this game as also. In metro I am getting 40-55 usually. I played it for about 30 minutes today and it didn't drop below 40 once. On borderlands 2 it was getting about 100-130fps. So I can tell it isn't an gpu issue. I don't understand what going on. Why won't my gpu have a higher percent usage on that game? With those games it also is getting a much higher % usage.