The advancement of multicore systems demands applications with more threads. In order to facilitate this demand, parallel programming models such as message passing interface (MPI) are developed. By using such models, the execution time and the power consumption can be reduced significantly. However, the performance of MPI programming depends on the total number of threads and the number of processing cores in the system. In this work, we experimentally study the impact of Open MPI and POSIX Thread (Pthread) implementations on performance and power consumption of multicore systems. Data dependent (like heat conduction on 2D surface) and data independent (like matrix multiplication) applications are used with high performance hardware in the experiments. Simulation results suggest that both implementations of more threads running in a system with more cores have potential to reduce the execution time with negligible or little increase in total power consumption. It is observed that the performance of MPI implementation varies (due to the dynamic communication overhead among the processing cores).