An escalating demand for improved heat dissipation from electronic components is driven by the imperative need to eliminate the accumulated heat that gradually builds up over time. In this study, a 3-D simulation was carried out to analyze the heat distribution performance of a heat sink based on PCM/NePCM. The heat sink was subjected to varying heat fluxes ranging from 3-7 kW/m2, and its performance was evaluated over time. The findings of the computational research indicate that using PCM assists in maintaining the heat sink base's temperature within lower bounds, and leads to uniform melting within the heat sink. Further, inclusion of Alumina nano particles integration in PCM enhanced the performance of heat sink. The percentage reduction in charging time of NePCM without fins (φ = 1%, 2.5% and 5%) in comparison to the Pure-PCM (φ = 0%) is 6%, 11% and 51% respectively at 6 kW/m2 input. At 6 kW/m2, NePCM with fin reduces the charging time by 85%, 87%, and 89% correspondingly for φ = 69%, 78% and 89% in comparison to Pure-PCM. Similarly, the significant reduction in charging time was found at φ = 2.5% and 5%, respectively, for different heat flux ranges (3 - 7 kW/m2) in comparison to Pure PCM. Thus, NePCM based heat sink displayed better heat transfer characteristic based on percentage reduction in charging time and temperature distribution.