  Primordial black holes in the mass range from $10^{-5}$ to $10^9$ g might
have existed in the early universe. Via their evaporation mechanism (completed
before Big Bang Nucleosynthesis), they might have released stable particles
beyond the Standard Model. We reconsider the possibility that such particles
might constitute the main part or a fraction of the dark matter observed today,
updating the impact on this scenario from warm dark matter constraints. If
sufficiently light, stable particles from primordial black holes evaporation
might also provide a significant contribution to dark radiation. We generalize
previous studies on this interesting dark matter and dark radiation production
mechanism, by including the effects of accretion and a possible amount of
entropy non conservation. We also discuss in some detail specific examples of
stable particle candidates beyond the Standard Model.
