1. A method for solving a linear equation system using a hardware-implemented extended solver, wherein a calculation precision is adapted in each iteration step of a solving process, the method comprising: storing, by one or more computer processors, data associated with a highest resolution of a three-dimensional finite element voxel model in a memory; performing, by one or more computer processors, on-the-fly interpolations using the data associated with the highest resolution of the three-dimensional finite element voxel model to a lower resolution than the highest resolution, wherein the on-the-fly interpolations are performed by a memory access unit during memory access to the data in the highest resolution of the three-dimensional finite element voxel model; and performing, by one or more computer processors, solving computations of the solving process in the lower resolution.