Huayuan Securities: Overseas is expected to gradually enter the era of all-liquid cooling. Currently, industry technologies are diverging and developing in parallel.

Huayuan Securities released a research report stating that the liquid cooling architecture and system value vary with chip power and rack architecture. The GB200 and GB300 computing trays shipped in 2025 will adopt a mixed cooling method of 85% liquid cooling and 15% air cooling. It is expected that the Vera Rubin NVL72 computing tray, which will begin shipping in 2026, will use 100% liquid cooling, while Rubin Ultra and Feynman will have higher power. Overseas markets are expected to gradually enter the era of full liquid cooling. It is worth paying attention to microchannel, diamond cooling, and two-phase immersion in the direction technology iterations, and it is recommended to focus on liquid cooling companies in related technologies. The main points of Huayuan Securities are as follows: Overseas markets are expected to gradually enter the era of full liquid cooling The liquid cooling architecture and system value vary with chip power and rack architecture. The GB200 and GB300 computing trays shipped in 2025 will adopt a mixed cooling method of 85% liquid cooling and 15% air cooling. It is expected that the Vera Rubin NVL72 computing tray, which will begin shipping in 2026, will use 100% liquid cooling, while Rubin Ultra and Feynman will have higher power. Overseas markets are expected to gradually enter the era of full liquid cooling. It is worth focusing on technology iteration 1 - microchannel Advanced cooling technology by placing a highly dense micro-scale cooling liquid channel network directly under or inside the cooling plate substrate. The channel width can range from tens of micrometers to hundreds of micrometers. The core technology evolution mainly reduces TIM or even eliminates it, and may even etch channels on the back of the chip, shortening the conduction path by 50% and reducing thermal resistance by up to 50%. It is worth focusing on technology iteration 2 - diamond cooling Akash Systems announced that it has delivered the world's first batch of NVIDIA GPU servers equipped with Diamond Cooling technology to Indian sovereign cloud services provider NxtGen AI Pvt Ltd. These servers are based on the NVIDIA H200 platform. Diamond is a wide-bandgap semiconductor with a thermal conductivity far superior to copper and SiC, and is an important path for NVIDIA's subsequent cooling technology. It is worth focusing on technology iteration 3 - two-phase immersion Liquid boiling phase change on the surface of the heat source, using vaporization to remove heat, the heat transfer coefficient is more than 10 times that of single-phase, theoretically the ultimate solution for high heat flux density. However, two-phase immersion relies heavily on low-boiling fluorine liquids, which poses significant environmental and cost challenges. Other possible cooling liquid solutions should be closely monitored. Recommendation to focus on liquid cooling companies in related technologies 1) Full system: Shenzhen Envicool Technology (002837.SZ), Guangdong Shenling Environmental Systems (301018.SZ), etc. 2) Cooling plate: YD Electronic Technology (301123.SZ), Shenzhen Cotran New Material (300731.SZ), Guangdong Suqun New Material (301489.SZ), Huizhou Speed Wireless Technology (300322.SZ), Shenzhen Hongfuhan Technology (300322.SZ), Sanhe Tongfei Refrigeration (300990.SZ), J.Pond Precision Technology (301326.SZ), Far East Smarter Energy (600869.SH). 3) CDU and other components: Ningbo Sunrise Elc Technology (002937.SZ), Guangzhou Goaland Energy Conservation Tech (300499.SZ), Feilong Auto Components (002536.SZ), Sichuan Chuanhuan Technology (300547.SZ), Sichuan Crun (002272.SZ), Yimikang Tech. Group. Co., Ltd. (300249.SZ), Jones Tech Plc (300684.SZ), SUGON DATA ENERGY (920808.BJ), Zhejiang Dayuan Pumps Industry (603757.SH), etc. 4) Cooling liquid: Ningbo Runhe High-Tech Materials (300727.SZ), Zhejiang Yongtai Technology Co .,(002326.SZ), Zhejiang Juhua (600160.SH), Guangdong Hec Technology Holding (600673.SH), Shenzhen Capchem Technology (300037.SZ), etc. 5) TIM: Shenzhen FRD Science & Technology (300602.SZ), Darbond Technology (688035.SH), etc. 6) Diamond cooling: Sf Diamond Co., Ltd. (300107.SZ), Beijing Worldia Diamond Tools (688028.SH), Henan Huanghe Whirlwind (600172.SH), Henan Liliang Diamond (301071.SZ), Sinomach Precision Industry Group (002046.SZ), HFZS (920725.BJ), etc. Risk warning 1) Technology iteration risks. Currently, multiple liquid cooling technologies are running in parallel, with different manufacturers trying different routes, which may ultimately lead to changes in the industry landscape and the elimination of some manufacturers. Rubin Ultra and Feynman architectures are speculations of Huayuan Securities Research Institute, there may be deviations from the actual situation. 2) Overseas customer testing progress is slower than expected. New liquid cooling technology products need to pass tests by end customers, and delays in end customers due to other issues may affect upstream suppliers' progress. 3) Geopolitical risks. If there are geopolitical risks, it may lead to delayed deliveries by some manufacturers.