With synchrotron X-rays, a dynamic ultra-small-angle X-ray scattering experiment on a partially aggregated gold colloidal suspension was performed. The preliminary X-ray photon correlation data could be compared favorably with the intensity-intensity time correlation function measured by means of a near-IR diode laser (lambda(0) = 790 nm) at equivalent scattering wave vectors. It should be recognized that the synchrotron X-ray source at NSLS was quite noisy. Nevertheless, the results demonstrate the feasibility of observing the motions of microstructures in polymer blends or colloidal systems by using the forthcoming third generation synchrotrons.