Oh sorry my mistake. Anyways I just tried it out (it downloaded sooner than I thought) and it gets 15 FPS for some reason from fraps but when it says 15 fps its in yellow not red howcome?
It's not switching to the 8870m. Right click desktop and click configure switchable graphics. If bf3 isn't in the recent programs list, then add it manually and change it to high performance.
As for fraps, it turns red when recording and yellow when you are not.