The embodiments of the invention relate to apparatus and method for reducing electromagnetic interference (EMI) and radio frequency interference (RFI) in computer systems via a chaotic wide band frequency modulation. The chaotic noise modulator, in one embodiment, comprises: a master cell to generate a control voltage corresponding to an un-modulated reference signal; and a slave cell having a chaotic signal generator to generate a random noise signal, the slave cell coupled with the master cell and operable to generate a modulated output signal in response to the control voltage.