AA/AF query

[jasong]

I've gotten back into Dolphin recently, checked out the progress it's been making - astounding really. Now what I've noticed is that if I play at my resolution, 1920x1200, pushing AA up to its limit in direct3d slows down the framerates quite a lot. In Wind Waker I go from 30fps solid to 20-25. So my question was, is this a CPU or GPU dependency; i.e. if I upgrade my graphics card will I get better AA performance? Or if I overclock/upgrade cpu will I get the additional performance? I'm currently running a 965be with 4gb ram and a gtx260 card. Assistance appreciated.