Watercooling your PC has been around for the longest time. The industry ushered in water blocks to the mainstream back in 1996 but the idea of cooling your PC with water actually stems from back in 1951. The first recorded personal computer with water and copper heat pipes was in the UNIVAC 1. Also known as the Universal Automatic Computer 1. The UNIVAC 1 was first announced by the Census Bureau back on 31 March 1951. However, installation of the device was only completed in the following December. It took them over a year to install the PC.
The UNIVAC 1 was a garage-sized PC that consumed a whopping 125kW of electricity. It included a robust water system with giant copper pipes that were fed throughout the device and fans to help further keep things cool. The water cooling system was so big that they actually deemed it a “refrigeration unit” called the CentraVac. Pumps would circulate the water through the system and the condensation tower was built outside the building. There were also fans outside the building which were used to pull in air.
We now have better cooling systems in our PCs than this entire building-sized water system. We can also build PCs in the comfort of our own home and they don’t take over a year to make. But what does a water cooler do to your PC and how do you know which is the best one for you? In this guide, I want to go through the basics of water cooling and explain that all.
For this guide, I am currently using the ASUS ROG Ryujin III alongside the Intel 14th-Gen Core i9 14900K CPU. It has been installed in the ASUS ROG Maximus Z790 Dark Hero motherboard built into the awesome ASUS Hyperion case.
So what does a PC water cooler do and what is the difference between air cooling and water cooling? Typically speaking, when building a PC or upgrading your cooler you’ll look for a unit called an All-in-One cooler, also known as an AIO cooler. All-in-one here means the cooler comes with all the parts needed to liquid cool your PC. This includes the radiator, the fans and the pump.
An AIO essentially works by absorbing the heat from the baseplate which is carried through one water pipe into the radiator. As the water flows, it picks up more heat and carries it. Once in the radiator, it gets cooled by being exposed to air. That cooled water is then sent back down the other water pipe back onto the baseplate to cool it and repeat the process.
The higher the RPM of the pump, the faster this hot water is sent to the radiator and returned as cool water to the baseplate. Fans also play a critical role in this process by blowing cooler air through the radiator helping cool the water down.
Some coolers get a bit more complicated and include reservoirs and advanced pipes. However, for this content, I am going to tackle mainly the standard AIOs which come in 120mm, 240mm and 360mm. You can also get 420mm coolers but those are quite niche still and enthusiasts usually know what they are picking up when buying one.
These numbers dictate what size your cooler is. Usually, they come with either 1, 2 or 3 fans and go up in size for each. A 1-fan cooler is 120mm, a 2-fan cooler is 240mm and a 3-fan cooler is 360mm. Each fan is 120mm. In the case of 420mm coolers, these radiators usually house 3 140mm fans.
The radiator for each size also increases to accommodate the fans. This is where finding the right cooler size comes in. Certain PC cases are limited in size and can only house 120mm and 240mm coolers. Larger PC cases, and the majority of them, to be honest, can easily fit 360mm coolers and down. So you’ll need to make sure your PC can accommodate your cooler size.
The best way to check this is to read the product manual on your PC case or the website for the brand that makes the case. This ASUS Hyperion gaming case, for example, can house two 420mm coolers but the case is kitted out with the ASUS ROG Ryujin III which is a 360mm cooler.
Getting the right cooler is also dependent on your motherboard. AMD and Intel motherboards have different cooler brackets so you’ll need to be sure the cooler you get includes the right bracket. Most coolers these days come with a range of different brackets to suit all different types of Intel boards so this isn’t as big of an issue as it was before. But always check what your CPU socket is on your motherboard and make sure your cooler comes with the right bracket mount.
These mounts are metal ring-like extras that will screw onto your motherboard and keep the CPU and cooler secure and the baseplate attached to the CPU surface. In a perfect world, all chip brands and motherboards should use the same mounts but sadly, that isn’t the case.
Another factor to consider when picking up a cooler is whether or not you plan on overclocking your CPU. The latest CPUs from Intel, for example, run incredibly hot and if you want a bit more juice from them, without going into liquid hydrogen tests, you’ll need a beefy cooler to manage this extra heat.
Coolers have also advanced now into a new tethered design. Previously, every fan on a cooler usually came with two wires. One to control the RGB and monitor the RPM and another to power the fan. Brands like ASUS have since switched this up. The Ryujin III cooler now comes with magnetic fan connectors that tether all three fans together while powering them and transferring all RGB and RPM information through a single wire.
This means things are clutter-free and so much easier to install. With one wire instead of six wires, this not only helps with cable management but also for new PC builders who could get overwhelmed by the number of cables.
When installing your cooler, brands are usually quite helpful with how they are all set up and placed. You’ll always want to install your cooler’s radiator on the top or the side of your PC case. Installing it at the bottom can cause some long-term issues.
Due to gravity, the pump will need to send the water up and down from the bottom of the PC. Instead of incoming water coming from the top and easily flowing onto the baseplate cooler, the pump needs to work on sending water up and down the entire time. As a result. they tend to not last as long. It is doable, but keep that in mind.
Coolers can also be monitored using built-in software such as the ASUS Armoury Crate. Software like this gives you a good glimpse at the current temperature of your cooler, and water and how fast the unit is working. You can also set up various presets to change the fan speed and performance depending on your scenario. Given that some pumps can get loud, you’ll only want them loud when you really need it.
While we are at it, let’s benchmark this Intel 14th-Gen Core i9 14900K CPU. The CPU includes a total core count of 24 with 8 Performance Cores and 16 Efficiency Cores. It packs a Max Turbo Frequency of 6GHz. But the base Performance Core Frequency out of the box is 3.2GHz while the Efficiency Core Frequency is 2.4GHz.
If you’re looking to easily overclock your CPU without worrying about core counts and technical knowledge, ASUS has its AI Overclocking feature which is likely the best bet here. For beginners, it offers a one-click experience where your system will automatically stress test your PC build, its cooling, performance and power limits.
Running it is very simple. You toggle the setting in the Armoury Crate and the PC will restart. Sometimes, the settings will ask for you to confirm the overclocking in the BIOS. Enter the BIOS and make sure all the enhancement tweaks show “AI Overclocking”. Once done, save the BIOS and restart the PC. It will then show overclocking has been activated.
I ran some Geekbench tests before and after the AI overclocking and you can see that after setting up the auto-run feature, the score did increase. The same goes for CineBench. Keep in mind that this was done with the most basic, user-friendly overclocking method around. A great way for new users to get more juice from their CPU.
Keep in mind that this specific Intel CPU is already overclocked out of the box so running a tool like this makes very little difference. That’s why the chip runs so hot. There’s very little room for improvement on a standard PC setup. You’ll need an advanced overclocking motherboard and need to tweak the per-core turbo multipliers to really see a difference.
So let’s recap. Be sure to get the right cooler size for your PC case. Always install your radiator on the front or the top of the case. Make sure you use the right mounting bracket and don’t be afraid to run some AI overclocking tools to get some more power from your PC. These tools will optimise the frequency and energy use of your PC to best suit your setup.
Thanks to ASUS for sending these components my way to play around with. You can find out more about the ROG Ryujin III on the official website here.
