This paper aims at the research on how the amount of internal nodes of a high productivity computer system using 2-D Mesh as its interconnection network influence the quality and speed of communication. In the experiments, we treat the InfiniBand adapter as the basic unit in 2-D Mesh topology, which can represent the interconnect network in our work more precisely, and use Opnet as the virtual experiment platform on which we conducted five experiments using 2-D Mesh interconnection structure with five different kinds of amount of nodes. The result should be helpful to the selection of the node topology which is of great importance to the establishment of a high productivity computer system. The following factors are taken into account to represent in a quantitative way the quality of communication and the scalability of the system: the latency of the transmission, the maximum throughput and the ratio of valid packets received.