When I say "lag" it doesn't mean "low FPS." it means "lag."

That being said, you can have very modern hardware and still get FPS drops in this game, it's so horribly inefficient and doesn't use multiple cores, so use a high resolution and have shadows on and even a pretty modern PC will drop the FPS. Hell, I can run 2 other games at the same time, neither one getting FPS drops, and FFXI's FPS is the only one that ever drops.