@FPSchris
This...
Tried this with tree and land shadows on and off, both same. Tried it with AA on and off, same results. Tried it worth morphological aa, same results. Tried it with vsync on and off, same results.
Really confused me, especially after you later posted this...
ok uh.. this is pretty messed up.
So I decided eh, what the hell, I'll just turn AA off completely and see what happens (I was just trying out morphological x16 super sampling b4 this).
To me AA off IS completely off. So anyway I had the same problem with fps with SSAA on my 5850s. In my case either I had set AA mode to SSAA when running less demanding games and forgot about it (most likely), or it was enable by default in one of the driver versions. I finaly figured it out when reading the reveiw on tomshardware for the 7970/7950.
From what little I have read SSAA is a performance killer for any video card, suited only for highend rigs that dim the lights when they hit load. If I were you I would try Adaptive MSAA, and if that is to much drop back to MSAA. But keep what stumped posted in mind I haven't messed with morphological filtering yet but I will soon 
@stumped
I also didn't know about the morphological filtering. Many thanks for the info.
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