The bidimensional Langevin for the symmetric fission of213At were solved without approximations using computer generated stochastic forces. Two dissipation mechanisms have been studied: a typical weak one (hydrodynamical viscosity) and a typical strong one (energy transferred to nucleonic motions from their changing self consistent potential). Calculated transient times (2.10−20sec or less) are comparable with those extracted from measurements of prescission neutron multiplicity. The kinetic energy distribution of the fission fragments was calculated for nuclear temperaturesT=1,2 and 3 MeV. A good agreement between theory and experiment was found for the variation withTof both its mean value and its variance. The calculated absolute values are however slightly lower than the empirical ones. At the same time it was also possible to test the validity of a deterministic (Lagrange) approach to the mean value of the prescission kinetic energy. The error involved was found to decrease with increasingTand to be less than 10%.