NVIDIA Pushes Liquid Cooling to 45°C, Slashing Data Center Water and Power Use

NVIDIA has announced that its latest generation of AI servers, the Rubin platform, can run cooling liquid at up to 45 degrees Celsius, or 113 degrees Fahrenheit. That is hotter than a typical hot tub, which sits at 38 to 40 degrees Celsius. The higher temperature is not a bug, it is a feature that enables the first 100 percent liquid-cooled AI infrastructure with no fans in the system.

The shift is dramatic. Traditional data centers have long relied on cold air to remove heat, with cooling alone accounting for up to 40 percent of a facility's electricity consumption. NVIDIA's new reference design, called the DSX AI factory, replaces that entire approach with a closed-loop liquid system that captures heat directly at the chip and rejects it through outdoor dry coolers. The result: a 50-megawatt hyperscale facility can save over $4 million annually in cooling-related energy and water costs.

No Fans, No Cold Aisles, No Water Consumption

The Rubin architecture eliminates two hallmarks of conventional data centers: the noise of cooling fans, which can reach 85 decibels, and the choreography of hot and cold aisles. Instead, a coolant mixture of 75 percent water and 25 percent propylene glycol flows through cold plates mounted directly on processors. The coolant enters at 45 degrees Celsius and exits at roughly 55 degrees, having absorbed the heat load. Because the liquid does all the work, the ambient air temperature in the data center is flexible. Warm summer air is fine.

NVIDIA's director of data center cooling and infrastructure, Ali Heydari, said the DSX design has zero water consumption. "With dry-cooler-based designs, it's a closed-loop system with no evaporative water cooling," he said. "Outside of maybe 1 percent of the year when we might need chillers in some climates." That compares to conventional cooling-tower systems that consume roughly 2.6 million gallons of water per megawatt per year.

• Cooling historically accounted for up to 40% of data center electricity consumption.
• Raising chiller plant temperatures by just one degree can cut cooling energy costs by about 4%.
• A 50 MW hyperscale facility can save over $4 million annually by moving to liquid-cooled infrastructure.
• Conventional cooling towers use about 2.6 million gallons of water per megawatt per year.
• NVIDIA's 45°C liquid cooling can reduce that to near zero, a 100% reduction in water use.

Industry Shift as Power Densities Make Air Cooling Obsolete

The transition is not optional for many operators. Motivair, the advanced cooling division of Schneider Electric, has worked alongside NVIDIA's product roadmap for nearly a decade. Its president and CEO, Richard Whitmore, said that once the watts per chip crossed a certain level, liquid cooling became mandatory. "Air cooling was no longer a viable option," he said. Every cloud provider and data center operator building for the Rubin platform is now making the switch.

NVIDIA's 45-degree liquid cooling architecture enables chiller-less operation in favorable climates, meaning mechanical chillers and noisy fans can be turned off for most of the year. The company's DSX reference design is now the standard for building AI factories, and the ecosystem of cooling vendors, including Motivair, is scaling production to meet demand. The next step: as chip power densities continue to rise, the coolant temperature may need to go even higher, but for now, 45 degrees is the new normal.