General-Purpose computing on Graphics Processing Units (GPGPUs) are becoming one of the most attractive computing platforms for handling high performance computing applications. This trend is more and more increasing especially with the help of new parallel programming models like CUDA and OpenCL, etc. The state-of-the-art GPGPU schedulers are likely to allocate as many as possible number of thread blocks into streaming multiprocessors. In fact, this is not always the optimal way to maximize the hardware utilization. This paper studies the drawbacks of the common-used round-robin scheduling at the thread block level. After that, we propose a new technique that can dynamically adjust the number of thread blocks to be assigned to streaming multiprocessors depending on the level of memory and interconnection network contention. Our simulation results on a 15-core GPGPU platform show that the proposed technique provides better performance over the baseline round-robin scheduling by around 6.3% on average.