In this paper, we investigate the co-design of multicore architectures and microfluidic cooling for 3D stacked ICs. The architecture is a 16 core, x86 multicore die stacked with a second die hosting an L2 SRAM cache. First, a multicore x86 compatible cycle-level microarchitecture simulator was constructed and integrated with physical power models. The simulator executes benchmark programs to create power traces that drive thermal analysis. Second, the thermal characteristics under liquid cooling were investigated using a compact thermal model. Four alternative packaging organizations were studied and compared. Greatest overall temperature reduction is achieved under a given pumping power, with two tiers and two microgaps with the high power dissipation tier on the top. Third, an optimization of the pin fin parameters including the diameter, height, and longitudinal and transversal spacing was performed. This optimization is shown to achieve up to 40% improvement in energy/instruction and significant reductions in leakage power.

Co-Design of Multicore Architectures and Microfluidic Cooling for 3D Stacked ICs [PDF]