  We have explored in three dimensions the fate of a massive white dwarf as a
function of different initial locations of carbon ignition, with the aid of a
SPH code. The calculated models cover a variety of possibilities ranging from
the simultaneous ignition of the central volume of the star to the off-center
ignition in multiple scattered spots. In the former case, there are discussed
the possibility of a transition to a detonation when the mean density of the
nuclear flame decreases below 2x10**7 g cm**-3, and its consequences. In the
last case, the dependence of the results on the number of initial igniting
spots and the chance of some of these models to evolve to the pulsating delayed
detonation scenario are also outlined.
