  The g_{YM} perturbed, non supersymmetric extension of the dual single matrix
description of 1/2 BPS states, within the Hilbert space reduction to the
oscillator subsector associated with chiral primaries is considered. This
matrix model is described in terms of a single hermitean matrix. It is found
that, apart from a trivial shift in the energy, the large N background,
spectrum and interaction of invariant states are independent of g_{YM}. This
property applies to more general D terms.
