We have used an intense coherent x-ray beam and a real time digital autocorrelator to study the low frequency dynamics of colloidal palladium in glycerol by x-ray photon correlation spectroscopy (XPCS). The translational diffusion was studied in the q range from 1.5 3 1023 to 6 3 1023 A21 and in the temperature range from 279 to 293 K. The measured relaxation rates were proportional to q2 and inversely proportional to viscosity as expected for a translational diffusion process. This experiment shows that XPCS can be performed in a wide time range (1024 to 100 s) and opens up a new opportunity for the study of the dynamics of nontransparent media. [S0031-9007(96)01912-6]