The parent poster is just either extremely confidently wrong or talking about a very different project from the one in the linked article - here's an article from 2005 with Figure 1 dating from (according to the article) 1965 (!!) showing the same CDU architecture shown in the chipsandcheese article: https://www.electronics-cooling.com/2005/08/liquid-cooling-i...
I do think Google must be doing something right, as their quoted PUE numbers are very strong, but nothing about what's in the linked chipsandcheese article seems groundbreaking at all architecturally, just strong micro-optimization. The article talks a lot about good plate/thermal interface design, good water flow management, use of active flow control valves, and a ton of iteration at scale to find the optimal CDU-to-hardware ratio, but at the end of the day it's the same exact thing in the diagram from 1965.
I do think Google must be doing something right, as their quoted PUE numbers are very strong, but nothing about what's in the linked chipsandcheese article seems groundbreaking at all architecturally, just strong micro-optimization. The article talks a lot about good plate/thermal interface design, good water flow management, use of active flow control valves, and a ton of iteration at scale to find the optimal CDU-to-hardware ratio, but at the end of the day it's the same exact thing in the diagram from 1965.