AC runs on high no problem, but arkham origins runs bad

Alright just want to get some input here.My specs are mid ranged, q6700 cpu,4gb ram, OC 7850, windows 7. I can run arkham city 1600x900 everything turned up except for physx, constant 50fps or more.

Now for arkham origins, I am sitting at 1600x900 resolution, everything turned off. Standing still I get maybe 25fps, in a fight it drops to 15. I have already turned off the dx11 options as it was messing up my cut scenes bad. I've tried lowering the resolution to 1280x720, and I still don't gain many fps. What is the deal? I've searched and read certain ATI drivers were best for arkham origins, tried those and still nothing.

I realize my CPU is somewhat old, and my card is only mid ranged, but still I don't understand why I can run arkham city so well, and arkham origins so crappy.

Thats what I have been reading, its a real shame. Origins appeals to me more, I havent finished either AA or AC, but I like the more grounded feeling origins.