CoolIT validates 15kW single-phase direct liquid cooling coldplate design

CoolIT Systems has developed a 15 kW single-phase direct liquid cooling (DLC) coldplate design, a capacity jump the company says is aimed at future ultra-high-density GPUs and AI accelerators.

CoolIT describes the 15 kW coldplate as delivering nearly four times the performance of earlier single-phase DLC coldplate designs. The company also says it represents more than 10x the cooling capacity required for the current generation of AI GPUs, and nearly four times the capacity of its previously disclosed 4 kW coldplate design from March 2025.

Technically, the 15 kW design uses CoolIT’s Split-Flow microchannel architecture. CoolIT validated the coldplate using a standard water-glycol coolant at 1.2 L/min/kW, and the company says the system-level thermal performance is suitable for 45°C warm-water cooling environments.

For data center engineers, the key takeaway is that single-phase, warm-water, direct-to-chip cooling keeps getting pushed upward in per-device heat removal claims. If these kinds of numbers hold up across real server mechanical constraints (manifolds, QD reliability, pump head, and serviceability), they expand the headroom for future accelerator packages without forcing a move to two-phase cooling purely on thermal capacity.

“Single-phase DLC is already cooling millions of AI accelerators today. This achievement shows it is also the architecture to cool AI infrastructure well into the future,” said Kamal Mostafavi, CTO of CoolIT Systems.

Dylan Patel, CEO of SemiAnalysis, said, “CoolIT’s work demonstrates that single-phase DLC has a clear path forward, giving both the semiconductor and data center industries greater confidence in the cooling architectures they can invest in.”

CoolIT also pointed to broader industry direction around warm-water liquid cooling, noting that NVIDIA has publicly highlighted single-phase DLC with 45°C supply temperatures as part of its next-generation AI platform direction. Separately, CoolIT said it is working on component coldplates and server architectures to extend single-phase DLC performance, including efforts to cool additional peripheral components and to target hot spots within advanced AI chips.

CoolIT’s 15 kW coldplate tech brief includes additional detail.