We apply a smooth coefficient semiparametric model to a unique high-frequency data set to examine the intertemporal pricing of personal computers. Furthermore, we test whether firms charge differential component prices for their top performance personal computers and whether premium firms charge both a premium for all their computers and a premium for their top performance ones. We find nonlinear effects in the pricing of personal computer components. We also find that firms in general do not charge differential prices for the components of their top performance computers. In addition, high-quality firms charge higher premia only for their most advanced products.