[AdMan]

They should have some kind of effect.

The things that stick out to me is to turn off Vsync

16Q AA is pretty much unnecessary, I'd test it by turning it off or on 2x and turn off supersampling to check fps, you should see a performance increase if it has anything to do with your graphics card's performance. I would also recommend allowing the AA to be application controlled rather than override application mode.

Threaded optimization can also be turned off for testing purposes only but remember to turn it back to auto if it has no effect. This can give you a hint if it's a multi-core problem.

game setting:

you should to easily be able to run
water=2 or 3
effects=1 or 2
forest=3

I've found sometimes bumping up certain settings actually shows a slight increase in performance oddly enough. But I use these settings on perfect mode with a 9800gt and my fps rarely drop below 60 (I also use xp tho). Sky setting also has a big effect on performance so I'd play with that.

If none of this helps I'd be inclined to believe it's a hardware issue

if it's a new rig or card also check your temps if airflow might be an issue