Liquid cooling
I'm thrilled that server farms are cooling their equipment more efficiently. That is obviously a Good ThingTM.
However, I do have one question : the amount of heat that needs evacuating does not depend on the manner in which the cooling is done. So, how is it that I am reading about economies ?
Granted, air cooling requires noisy fans and proper airflow, which is not always obvious to ensure. Liquid cooling is easier since the heat is leaving through a pipe, not just through the rules of thermodynamics, so it's a sight easier to know what you're doing, but in the end, there is still a fan pushing (or pulling) air through a grill, and that's where the cooling is happening.
Far be it from me to knock liquid cooling. I have been an active proponent of it for almost two decades (aka, before it became common), but the amount of heat to evacuate does not change, even the operating comfort does.
When I adopted liquid cooling for my first AMD Thunderbird, it made a world of difference. My home office was silent. The only noise left was the soft whirr of a pair of hard disks. It was astonishing, and I never went back to pure aircooling.
Nowadays, my home rig has watercooling on the motherboard, on the graphics card and, of course, I bought a CPU cooling kit with a ginormous radiator. So I have a 3-fan radiator for my GPU (which, in all honesty, never makes a sound) and a two-fan radiator for the CPU (which makes more noise, annoyingly), in addition to the chassis and PSU radiators. Still, I will never go back to pure aircooling.
But the heat is still there. It still needs to be taken away. The only advantage of watercooling (apart from reduced noise levels) is that you don't have to rely on iffy air thermodynamics. I do not see any other gains.