In our recent group test of pre-assembled liquid cooling sets we learned that these are capable of providing more cooling than air coolers. It also turns out that they are louder than air coolers for the simple reason that there are more components that can cause noise, the pump for example, and there's no way around this. It's good news for overclockers that are more interested in squeezing the maximum performance out of their system than having a super-quiet PC. A good liquid cooler provides more overclocking potential than an air cooler.
Overclockers are not the only ones that can benefit from liquid coolers, however. The heatsink of a liquid cooler takes up much less space than your typical CPU tower cooler. This can potentially benefit the air flow and therefore the temperatures. We put this theory to the test, does water cooling improve the air flow and thereby lower the temperature inside a PC?
Liquid cooling in practice
To find out once and for all we took one of the best liquid cooling sets from our recent test, the Corsair H100i, and set up a real-life test to compare it with the best air cooler we've recently tested, the Noctua NH-D14. The test system we used consists of an Intel Core i7 3960X processor, ASRock X79 Extreme4 motherboard, 16 GB Corsair Vengeance LP DDR3-1600 RAM and an AMD Radeon HD 7770 graphics card built into a Corsair Obsidian 550D. This is a silent chassis designed for liquid cooling.
When we were installing the coolers, we right-away noticed one advantage of the liquid cooler. Good air coolers are quite large, and the Noctua NH-D14 just barely fit inside the Corsair Obsidian 550D. There were only a couple millimetres left between the graphics card and the hooks that hold the fans to the heatsink on the CPU. Large tower coolers can also be an obstacle to RAM modules, so we used special low-profile Vengeance modules. Replacing these modules is not possible as long as the cooler is attached. A liquid cooling set doesn't pose these problems.
That's because the heatsink including the pump of liquid cooling sets are typically much smaller, you really end up with much more space around the CPU as you can see on the photos below.
But the air cooler did fit, which is what matters. If you have a deluxe chassis with transparent side window it is true that a liquid cooling set looks much better. Keep in mind that not all chassis can house a radiator without using a steel saw, especially if you have 240mm and larger radiators.
A world of difference between using a high-end air cooler or liquid cooler.