I run two AMD 7800 graphic cards cross-fired and with an unacceptable frequency am experiencing a drop in frame rate for 5-30 second and when it picks up there's usually something missing, mount, mob, NPC body(just a floating head). This has been occuring for quite some time, and from the looks of it to a lot of people.

I would like to know if there is any in-game graphic setting i need to fix or something, currently nothing seems to be working.