Escalating cooling demand in electronic devices necessitate the development of an efficient cooling solutions that can be realized in practical systems. A novel electronics cooling solution based on Phase Changing Material (PCM) is presented which can overcome the operational difficulties of flow boiling in microchannel employed in an electronics cooling module. A system dynamics modeling and simulation of a miniature electronics cooling module employing PCM assisted flow boiling of coolant in rectangular microchannel has been carried out. A state space model for the simultaneous solution of conjugate heat transfer in solid, PCM and liquid domain is formulated. Simulations performed based on the developed model shows that the PCM storages help to prolong the favorable boiling heat transfer conditions in the microchannel.