An important trend in the research of many ASCI groups is to focus more on the problems of heterogeneous Grids. DAS-1 and DAS-2 were homogeneous systems, allowing controlled experiments on the performance of algorithms, languages, and systems. These experiments have given much new insight that would have been difficult to obtain on heterogeneous Grids. However, now that this fundamental research has successfully been completed, many groups shift their orientation towards heterogeneous Grids and their inherent problems, so there now is a strong desire for a more heterogeneous testbed. In addition, different ASCI groups have different requirements for the local interconnect, CPU speed, memory size, etc., which also argues for a more heterogeneous system. Based on the different requirements from the participants of DAS-3, the hardware configuration of each cluster is not exactly the same. The following table shows the detailed configuration at each site.