I ran the fully functional Perfectdisk 30-day free trial...and guess what? Not one noticeable frame rate gain. It is one of those pseudo-make me feel better about my fsx performance things. Bottom Line: You won't get perfect FPS unless you have a quad core running 6GHZ with 8 gb of the fastest memory. FSX was released at least a decade before the computers were built that would be able to perfectly handle it. I overclocked my Intel Q9650 from 3GHZ stock to 4.2GHZ...to 1gb videocards on sli, and I get "playable" framerates.