Under the Analysis tab in the Project Settings dialog, you can choose the Matrix Solver Type. There are two options available:
Jacobi Bi-Conjugate Gradient
Gaussian Elimination
By default, Examine2D uses the Jacobi Bi-Conjugate Gradient method to solve the matrix representing the system of equations defined by your model. The Jacobi Bi-Conjugate Gradient method is an iterative solver, which is very efficient for solving large matrices. The matrix size is dependent on the number of boundary elements and the element type (constant, linear, quadratic).
For a typical Examine2D model, you will not notice any difference in computational speed, whether you choose Jacobi Bi-Conjugate Gradient or Gaussian Elimination as the matrix solver.
In rare cases, the Jacobi Bi-Conjugate Gradient method may not converge to a solution (an error message will be displayed if this occurs), in which case you can specify Gaussian Elimination as the matrix solver.