With that configuration your only options are to either clock down the video card a bit (some people have said this has evened-out frame rate) but really the game really only makes use of one CPU core, and your CPU is in fine. The video card depends on the driver and settings that override the game's settings.

I have a much weaker card currently, and the frame rate drops noticeably around very large FATE groups (30 people or so) and large areas of water. The latter is because HDR is computationally expensive. The former is something that every MMO game in existence does.