Screen Freezes.

[Deleted]

Im currently, and had for a while had a problem that my screen freeze during some raid fights during ceratain parts, aswell as in pvp during some spells..
Currently known:

Rajh - recharge phase
Atramades - when someone hits the gong in air phase.
Darkweaver Syth - Summoning elementals.
Trash before Elementium Monstrosity, flamestrike.

Moonkin aoe silence.
Dk Hungering cold.

Im Running Hd radeon 6850 with latest graphics drivers and everything on ultra but view distance and shadows.
im using the SET gxApi "d3d11" string in my config aswell as - d3d11 in my launched shortcut
60fps in orgrimmar and i never go above 60fps anywhere else.

anyone knows what may cause this problem, its quite annoying and id like to keep running my game in ultra without having these spikes.?

Edit: tried running darkweaver syth with everything on low. same result.

2nd edit: Looks like the patch fixed it.