Closed-loop liquid cooler roundup: 9 AIO coolers reviewed

  • Published in Cooling reviews

Fractal Design S24

Fractal Design updated the Kelvin AIO series earlier this year. While it looks technically the same as the previous generation, several small tweaks have been made to the series. Unlike the flashy, bright and colorful all-in-ones we’ve covered until now, the S24 is unassuming in design, having a glossy lid on the pump, but no added LEDs or clear tubing / reservoir windows.

Fractal Design Kelvin S24 - AIO cooler

One thing worth mentioning is that this is one of the most customizable AIO in this round-up, as it allows you to add extra radiators, custom-loop reservoirs or GPU blocks.


At first glance, Kelvin has a standard looking radiator – similar to Nepton’s or Water 3.0 Extreme’s. The single noticeable difference would be the smaller fin per inch count (only 14FPI) that lends itself to better airflow through the radiator at the expense of surface area.

Fractal Design Kelvin S24 - Radiator

However, the radiator is made entirely out of copper, and is in fact, very similar to Alphacool’s NexXxos ST30 radiator. Measuring 30 x 124 x 275mm, the radiator supports up to two 120mm fans on each side.


The 320mm rubber tubing is not special in any way, but it is fitted with anti-kink spring coils that prevents any kinks while installing quite effectively. 

Fractal Design Kelvin S24 - Tubes

The diameter is 11mm outer and 8mm inner, and it measures up to 320mm. What's interesting is Fractal Design decided to use black-painted brass fittings (the kind you would find in custom loops) to keep everything in place.

Pump & Waterblock

The downplayed CPU-Block features a ceramic bearing pump, with a 2400RPM pressure, resulting in a maximum flow-rate of 120l/h, and a rated lifespan of 50.000 hours.

Fractal Design Kelvin S24 - Pump

The base is of copper build, with copper screws attached to it. It’s not polished to a mirror sheen, but close enough.

Fractal Design Kelvin S24 - Copper Base

As most modern AIOs, the coldplate features micro-channels for better heat transmission. The plate is sealed with rubber rings, ensuring the water flows directly onto the copper base and does not escape in other directions.


Two seven bladed HP Silent Series 120mm fans dynamic bearing fans are included in the package. These feature PWM controls and an RPM range of 500-2000RPM.

Fractal Design Kelvin S24 - Fans

These should put out 87.6CFM, at a pressure of 2.30mm H20. Granted, they’re not the most silent fans used by a cooler in this round-up, having a noise level rating 32.2dB(A).


In terms of clearance, Fractal Design eats up even less space than Silverstone's TD02-E. The waterblock / pump are small enough to be fitted even on smaller boards, while the radiator (albeit slightly thicker than the 27mm variants we checked until now), shouldn't cause any issues at installation.

Fractal Design Kelvin S24 - Installed

Sadly, the installation procedure is unpleasant. Following the instructions will not be difficult, but mounting the waterblock will. You see, the mechanic uses a backplate that features no dedicated slots on its spacers, which means the nuts are free-moving. Since these are so small - I often had them pop out of the motherboard while trying to mount the screws. Still, on paper, to mount the AIO cooler all you have to do is:

1. Install the plastic backplate onto the motherboard;
2. Lock-in the two mounting-brackets onto the waterblock;
3. Attach the block onto the motherboard and tighten the spring fitted bolts and screw in;
4. Connect the pump 4-pin connector to & the fans’ 4-pin connector to the appropriate header;

« Prev
9/13 Next »

Deprecated: Non-static method modSlideLikebox::getLikebox() should not be called statically in /var/www/clients/client1/web2/web/modules/mod_js_social_tabs_slider/mod_js_social_tabs_slider.php on line 14

Please fill in the following form to contact us

* Are you human?