Hy i have some trouble and i dont know , is that my pc or some driver issue

i play skyrim on a resolution of 1080p and ultra settings FXAA on 16xAF 8xAA

The Fps are very bad it goes from 40-60 indoor(not the prob) to 20-30 outdoor (thats the prob) andfrom time to time its laggi ....BF3 ultra settings goese from 60-90 Fps

My System

Intel core i7 950 3.02Ghz
12 Gb DDR3 Gskill RAM
Saphire Readon HD6990 4Gb
CCC 11.10 WHQ
Windows 7 64bit

is that normal?

Turn down your settings, report results.

the first picture is with maxed settings 8xAA and FXAA ...i find this place and there the Fps go dow. http://www.pictureupload.de/originals/pictures/121111154558_TESV_2011-11-12_15-44-54-18.jpg FPS: 19

the next picture at the same place without FXAA and 4xAA http://www.pictureupload.de/originals/pictures/121111154953_TESV_2011-11-12_15-49-13-34.jpg FPS:19

and the next again same place with FXAA on and 8xAA Shadows option High..not ultra http://www.pictureupload.de/originals/pictures/121111155632_TESV_2011-11-12_15-55-47-73.jpg FPS: 24

on this place i took the pitcures ...i turn around and look at the Mountains and there i have 58-60 fps

PS: sry for this english but not my languege

i only think with this graficcard i await a little bit more power