A porous medium saturated with water-ZnO nanofluid is used for thermoregulation by natural convection of a cubic electronic component contained in a tilted hemispherical cavity. The ratio between the thermal conductivity of the porous medium's solid matrix and that of the base fluid varies between 0 (without porous media) and 70. Moreover, the volume fraction ranges from 0 (pure water) to 10% while the component generates surface heat flux leading to high Rayleigh number values reaching 7.29 x 10(10). The three-dimensional numerical approach achieved through the volume control method with a monophasic model was used to quantify the free convective heat transfer. The average Nusselt number was determined for several combinations of the four influence parameters mentioned above. The results show that from an inclination of 90 degrees, the tilt angle of the enclosure has little influence on the Nusselt number. It strongly increases with the ratio growth of the solid-fluid thermal conductivities but it fades from a critical ratio whose value decreases with increasing the Rayleigh number. Influence of the fraction volume is moderate throughout the treated range especially for large nanoparticles concentrations. This correlation clearly highlights influence of these parameters and allows the correct thermal design of the considered electronic equipment.