Not strictly. Yes, the above is correct, but to know which your computer is using, check the lights in the middle above the keyboard. If the orange one is on its using your 660m, if the green one is on it's using your internal gpu. The reason I say not to rely on the VGA button alone btw, is because if you already have an application open (like steam) that optimus see's as a dedicated GPU application, then pressing the VGA button alone won't suffice, you'd have to also exit steam and relaunch it.