-Settings-Game Settings-PS Upscaler (OFF) PS Smoothing (OFF)
-Settings-System Settings-Display [What's New] (OFF) Notification Messages (DO NOT DISPLAY)
-Settings-Display Settings-Cross Color Reduction Filter (OFF) RGB Full Range (Limited) Y Pb/Cb Pr/Cr Super-White (OFF) Deep Color Output? (OFF)
Many people confirmed the seemingly improvements.
And it could make sense, since those turned off features consume a lot of ram, because the PS3 OS is still running in the background, even when you play
From:
http://www.youtube.com/watch?v=Gg7j11_tlBY

(even turned off all the autosave functions)