  Starting with a spectral triple one can associate two canonical differential
graded algebras (dga) defined by Connes and Fr\"ohlich et al. For the classical
spectral triples associated with compact Riemannian spin manifolds both these
dgas coincide with the de-Rham dga. Therefore, both are candidates for the
noncommutative space of differential forms. Here we compare these two dgas and
observe that in a very precise sense Connes' dga is more informative than that
of Fr\"ohlich et al.
