Huge FPSdrops?

Having a few problems with enemy territory lately firstly i'm getting huge fps drops on the oasis time demo i have easily 210+ fps but in game it's a different story doing com_maxfps 0 my fps is never reaching above around 200 even in low cpu maps like supplydepot2 where i could get 333 fps and more up to wild numbers easily anyone else having the same problems?
i'm running an amd 4000+ @ 2.8GHz, 2x512 dual channel corsair xms twinx @ ddr470 2-3-3-6 and a 6800 gt @ 440/1150 msi k8n neo2 platinum any ideas why i'm not getting my normal high fps?