Maximum PC - UK (2020-05)

Main Ingredients

Reservoirs

& Pumps

Fans

Radiators

Although we like

splitting our reservoir

and pumps, combi units

are far easier to use.

Reservoirs come in all shapes and sizes.

Most common are cylindrical tubes with

ports on the bottom and top, or integrated

with a pump. However, distribution plates,

5.25-inch bay reservoirs, and rectangular

reservoirs are also available.

As for pumps, almost all of them are

manufactured by a single company, Laing,

then distributed to liquid-cooling brands,

which house them in their own products.

There are two main pump types, the D5

and the DDC. The D5 is a large form factor

pump, ideal for liquid-cooling systems

with multiple radiators, reservoirs, and

waterblocks, whereas the DDC has a far

smaller footprint, and is ideal for small

form factor and ITX PCs.

We recommend fans with a high static

pressure and a low noise rating. One of

the best things about liquid cooling is it

gives you a smoother way of dissipating

heat by using more fans at lower RPMs.

Typically, with a CPU tower, the heated

vapor needs to be cooled immediately,

so it can do its job again, and it spikes

in temperature as soon as the CPU is

under load. With liquid cooling, because

there’s so much coolant being pushed by

the pump, the coolant has a far higher

thermal capacity, giving you time to

cool it down via the radiator’s far larger

surface area, with more fans. So, you can

run more fans at lower RPMs, reducing

Radiators are the primary means for you

to remove heat from your system. Most

radiators come in sizes that are derivatives

of either 120mm or 140mm, in the same

manner that PC case fans do. So, you get

120/140mm, 240/280mm, 360/420mm,

and 480/560mm radiators, going from

one fan all the way up to potentially four

fans per side. On top of that, they can be

far thicker than a standard AIO radiator.

Taking EKWB as an example, its SE (slim

edition) 120mm radiators are 28mm

thick—that’s about the same thickness

as the radiator used in the Corsair H100i.

Most regular custom loop radiators are

noise, while still extracting heat from the

coolant adequately to keep everything

running smoothly.

For most of our liquid-cooled builds,

we set the fans to 30–50 percent of their

total RPM and leave them there. This is

fantastic for those frustrated with loud

fans or in noise-sensitive environments.

Take a Corsair ML 120 Pro, for example.

At max speed, it hits 37dB(A), but drop it

down to 1,000rpm (half its max speed),

and it only reaches 18.5dB(A)—that’s the

difference between a busy office and a

whisper, and yet it’ll still be pushing close

to 2.1mmH 2 O, which is more than enough

to cool our low fin density radiators.

considerably thicker

than that, with

the average being

around 40mm or so.

When it comes to

radiators, there are

two things to take

note of: Firstly, you’re

going to want at least

120mm of surface area

per component you want to cool (double

that for overclocking), and secondly, you

need to pay attention to fin density, or FPI.

The higher the density, the more static

pressure you need to effectively push air

through it. In the case of that H100i we

mentioned earlier, it has a fin density of

around 21 fins per inch, compared with a

240mm super-thick XE radiator from EK,

where you’re looking at just 16fpi.

liquid cooling

26 MAXIMUM PC MAY 2020 maximumpc.com