The design of high-performance servers has always been a challenging art. Now, server designers are being asked to explore a much larger design space as they consider multicore heterogeneous architecture and the limits of advancing silicon technology. Bringing automation to the early stages of design can enable more rapid and accurate trade-off analysis. In this paper, we introduce an Early Chip Planner which allows designers to rapidly analyze microarchitecture, physical and package design trade-offs for 2D and 3D VLSI chips and generates an attributed netlist to be carried on to the implementation stage. We also describe its use in planning a 3D special-purpose server processor. © 2011 EDAA.