NVIDIA's Rubin AI Infrastructure Shifts to 100% Liquid Cooling at 45°C
The cooling liquid inside NVIDIA's newest AI servers runs hotter than a hot tub, and that's precisely the point. NVIDIA Rubin liquid cooling operates at up to 45°C, making the Rubin generation the world's first AI infrastructure platform to run every chip and every networking component on liquid alone, with no fans anywhere in the system.
Built around the NVIDIA DSX reference design, NVIDIA's framework for designing and operating full AI factory infrastructure, the platform is now the standard for operators building Rubin-based compute.
Near-Zero Water, Sharply Lower Energy Bills
Cooling has historically consumed up to 40% of a data center's electricity. According to NVIDIA's blog post, a 50-megawatt hyperscale facility can save over $4 million annually in energy and water costs by switching to liquid-cooled infrastructure.
Water savings tell a similar story. Conventional cooling-tower systems consume roughly 2.6 million gallons of water per megawatt per year. The Rubin design cuts that figure to near zero in favorable climates, where dry cooler technology replaces evaporative water cooling almost entirely.
"The NVIDIA DSX reference design for AI factories has zero water consumption," said Ali Heydari, NVIDIA's director of data center cooling and infrastructure. He described a closed-loop system with no evaporative water cooling, outside of maybe 1% of the year when some climates might still need chillers.
Why Hotter Coolant Actually Works
The higher the coolant temperature, the easier it becomes to reject heat outdoors without running mechanical chillers. The design leans into that trade-off on purpose.
Coolant flows through cold plates mounted directly on processors, entering at 45°C and exiting at roughly 55°C after absorbing heat at the chip surface. Performance stays fully intact because the cold plates maintain device temperatures within validated operating limits, regardless of what temperature the coolant arrives at.
Because no component depends on cooled air, outdoor dry coolers can handle heat rejection for most of the year. In favorable climates, chillers may never need to turn on at all.
Richard Whitmore, president and CEO of Motivair, the advanced cooling division of Schneider Electric, put it plainly. "In the right geographic location, with the right system design, you don't need any refrigeration equipment," he said. "You can just put big radiator coils outside and use the air temperature for all your cooling."
Fewer Racks, Less Noise, New Possibilities
Traditional data centers run fans loud enough to require ear protection, with noise levels at or above 85 decibels. Rubin servers have sealed front panels, no fans, and a significantly smaller physical footprint. A system that once occupied six rack units now fits in two.
Waste heat from Rubin-based AI factories could also be repurposed to heat nearby commercial or residential buildings, according to NVIDIA, adding a secondary layer of sustainability potential beyond energy savings.
For Rubin customers, data center energy efficiency at this scale is no longer a roadmap target. The real question now is how fast warmer-climate operators can engineer their way toward that near-zero-water mark.
Read the full technical breakdown: NVIDIA Blog: The 45°C Breakthrough to Cool AI's Biggest Machines.