  We investigate the classical geometry corresponding to a collection of
fractional D3 branes in the orbifold limit of an ALE space. We discuss its
interpretation in terms of the world-volume gauge theory on the branes, which
is in general a non conformal N=2 Yang-Mills theory with matter. The twisted
fields reproduce the perturbative behaviour of the gauge theory. We regulate
the IR singularities for both twisted and untwisted fields by means of an
enhancon mechanism qualitatively consistent with the gauge theory expectations.
The five-form flux decreases logarithmically towards the IR with a coefficient
dictated by the gauge theory beta-functions.
