I have a short checklist in link #5 in my sig
upd
If you stick to 30 fps probably you have triple buffering off. Create a game(!) profile in ATT and switch triple buffering on (read the help file for ATT.) Then you can reduce tex quality and mip map quality from "high quality" to "quality" or lower in ATT creating a 3D(!) profile. Switch all optimization checkboxes on, etc, etc. Do not remember everything listed in my checklist myself. lol.