Solving an ill-conditioned, sparce unsymmetric linear system

Hi,

I am trying to solve a set of linear equations for a material model through c++.

The system was already solved in Mathematica using Krylov method (BiCGStab).

Through Mathematica, I found that the condition number of the stiffness matrix is in the range of 10^8.

Thus I understand it is ill-conditioned. It is also unsymmetric.

Now I have already tried the direct solver Pardiso with scaling. But the data did not match the one from Mathematica.

I want to know if there is a better approach to solve this system. Also should I trust the Mathematica results, considering the nature of the linear system ?

Please help, any advice is much appreciated.

Roshan