Just adding my two cents here to say I’ve tried all of the in-game graphics/ATI Catalyst Control Center setting adjustments listed here and in the sticky post, but still suffer from single-digit frame rates when turning the camera or, when standing stock still, every 6-10 seconds. I see this frame rate drop happen even on the character select screen, and I’ve been playing since beta with no comparable issues.
I’m using an ATI GeForce 5800 series card on an ASUS G73JH laptop, not expecting 60 fps here, but I have gotten a reliable 30+ until recently.