New Results in N=2 Theories from Non-perturbative String

We describe the magnetic phase of SU(N) (Formula presented.) super-Yang-Mills theories in the self-dual (Formula presented.)-background in terms of a new class of multi-cut matrix models. These arise from a non-perturbative completion of topological strings in the dual four-dimensional limit which engineers the gauge theory in the strongly coupled magnetic frame. The corresponding spectral determinants provide natural candidates for the (Formula presented.)-functions of isomonodromy problems for flat spectral connections associated with the Seiberg-Witten geometry.