Having -any- tooltip popup causes my fps to drop down to 1 and stay there until I shake it away.

Yeah I've been having the same problem, even from the games starting menu the animations run smooth until a tooltip box pop's up, then its 1 frame per second at best but returns to normal when you move it away.
it's also effected the game itself as a lot of the combat animations are lagged to hell and back too, ever seen a chaos marine throw a grenade at 1 frame per second? its cool seeing the animation frames but....