Game freezing after patch

Since the Wintersday content patch, my game has been freezing or dropping to <1 FPS in several places. Places where the freeze has happened:-The Wintersday plaza area, inconsistently.-Istan (seems to be triggered by being on a mount near Palawadan or GH walls.)-The snowman lair raid, at the final boss (When I closed the game and loaded back in, and my downed character was placed back at the start of the instance, the game continued to intermittently freeze.)-Cliffside fractal, at the final boss (I haven't tried any other fractals.)-Forest of Niflhel, while fighting Svanir.

Lowering my graphics settings to minimum has not helped.