Benchmarking Two-Phase vs. Single-Phase Cooling

This technical report presents a detailed comparison of two-phase and single-phase direct-to-chip cooling technologies on a Dell PowerEdge XE9680L server equipped with NVIDIA B200 GPUs. The evaluation, conducted by an independent third-party systems integrator, aimed to quantify the performance differences between the two cooling systems under identical conditions. The results indicate that the NeuCool two-phase cooling system maintained GPU cold plates up to 19°C cooler than the factory-installed single-phase system and achieved lower junction temperatures at the full-system level. The report outlines the methodology used for testing, which included varying GPU core power and simulating AI workloads to produce a comprehensive thermal performance map. The findings highlight the advantages of two-phase cooling in terms of energy efficiency and thermal management, particularly as facility water temperatures rise. The report concludes that two-phase cooling is a significant advancement for AI data centers, offering lower total cost of ownership and enhanced cooling capabilities for next-generation hardware.