  We study static AdS star in generic dimension. The dependence of the mass
limit to the bulk fermion mass is explored. In the bulk conformal limit, the
mass limit saturates at a value identical to the mass limit of a radiation star
or the AdS space filling with pure radiation. The temperature and entropy of
the degenerate AdS star in the bulk conformal limit is zero in contrast to the
radiation star. Holographically, the universal mass limit corresponds to the
upper limit of the deconfinement temperature in the dual gauge picture. The QGP
at this temperature is dual to the large black hole and the heat capacity is
positive. When the fermion mass increases, the mass limit falls into the range
of the small black holes. We found that even though the small black hole has
negative heat capacity, the AdS box allows possibilities that it remains in
thermal equilibrium with the radiation as long as the size of the black hole is
not smaller than a critical size. Consequently, the dual QGP with negative heat
capacity can be produced and remains stable thermodynamically at temperature
below a saturation temperature $T_{2}$. The QGP with negative heat capacity
produced at higher temperature will still condensate completely into a gas of
confined hadron.
