The main point of Linpack is to solve systems of linear equations of the given size (Problem Size). It is designed as a benchark to test the performance of a system in GFlops - billions of floating point operation per second. But being highly optimized it is also the most stressful CPU testing program to date and is a great tool in determining stability/instability of a CPU, outperforming other CPU testing software at least time-wise. One and the same system of equations is solved repeatedly; if all results match each other - the CPU is stable, otherwise the instability is obvious, since the same equations system cannot produce different solutions.