We present a detailed study of the dynamics of cadmium sulfide nanoparticles suspended in polystyrene homopolymer matrices using X-ray photon correlation spectroscopy for temperatures between 120 and 180 degrees C. For low molecular weight polystyrene homopolymers, the observed dynamics show a crossover from diffusive to hyper-diffusive behavior with decreasing temperatures. For higher molecular weight polystyrene, the nanoparticle dynamics appear hyper-diffusive at all temperatures studied. The relaxation time and characteristic velocity determined from the measured hyper-diffusive dynamics reveal that the activation energy and underlying forces determined are on the order of 2.14 x 10(-19) J and 87 pN, respectively.