The heat transfer characteristics of two boundary layer flows past an isothermal plane surface adjacent to a saturated Darcy-Brinkman porous medium is compared to each other in this paper. The flows are driven either by a stretching of the adjacent plane boundary, or by an external pressure gradient. It is found that below a threshold value of the modified Prandtl number , the Nussselt number in case of the pressure gradient-driven flow is larger than in case of the wall- driven flow, while for the flow driven by the moving wall provides a more efficient heat transfer mechanism. The dependence of on the Darcy number is also discussed in detail.