Different methods for the numerical integration of evolution dissipative partial differential equations are tested with the Kuramoto-Sivashinsky equation. Discretizations in space include Galerkin and nonlinear Galerkin methods. For integration in time three different codes are used, including standard stiff ODE methods. Numerical tests show that sta nda rd codes for stiff ODE ren der a gain of computing time of several orders of magnitude with respect problem-tailored methods. (C) 1995 Academic Press, Inc.