  We present early results from a lattice QCD study seeking a bound
$H$-dibaryon using $N_f=2$ flavors of $O(a)$ improved Wilson fermions and a
quenched strange quark. We compute a matrix of two-point functions using
operators consisting of the two independent local products of six
positive-parity-projected quarks with the appropriate quantum numbers, which
belong to the singlet and 27-plet irreducible representations of flavor SU(3).
To expand this basis, we also independently vary the quark-field smearing, and
apply a new scheme to reduce the noise caused by smearing. We then find the
ground-state mass by solving the generalized eigenvalue problem. We show
results from ensembles with pion masses 451 MeV and 1 GeV, and compare with
other lattice calculations.
