The volt and watt settings don't affect each other. That is to say, if you're in VW mode it does not matter what volt-setting you're on, and vice versa. However, this allows for two different "power settings" to be "programmed" on the SVD. For example, having the VW set to 9W and the VV to 3.4, and you can switch between high and low power to the atomizer with a simple double-button press and hold :-)