260 GTX Wont work in perfect Mode

[KG66_Manta]

I just cant figure this out, I was running a 8800GTX and could use perfect mode to have that great looking water and still be a t 60fps.

I have now purcahsed a new Asus 260 GTX and if I select perfect mode my frame rate drops from 60 to about 16.

I have tried different drivers and also have re-installed the game and still no luck.

Any ideas as it looks like I am going to have to rip out the 260 Gtx which will really suck