PVM is an inexpensive, but extremely effective tool which allows a researcher to use workstations as nodes in a prallel processing environment to perform large-scale computations. The numerical approximation and visualitzation of seismic waves propafating in the earth strains today's largest supercomputers. We prenet timings and visualization for large earth models runon a ring IBM RS/6000's whicth illustrate PVM's capability of handling large-scale problems.