Benchmarking Performance of Parallel Computers Using a 2D Elliptic Solver Ivan Lirkov, Svetozar Margenov, Marcin Paprzycki It was recently shown that block-circulant preconditioners have very good numerical properties when applied to a conjugate gradient method used to solve sparse linear systems arising from 2D elliptic problems. In addition the early experimental data collected for small and medium size systems solved on parallel computers with limited number of processors indicated potential for good parallel efficiency. The aim of the presentation is to summarize and compare the performance of the MPI-implemented elliptic solver across a wide variety of modern parallel computers (including, but not limited to: SGI Power Challenge 8000, SGI Power Challenge 10000, SGI Origin 2000, HP-Convex SPP-2000, IBM SP-2).