I am testing a flagship cooler from the new generation of Liquid Freezer from ARCTIC. This is Liquid Freezer III 420 Black. This cooler is also available in A-RGB fashion and comes in black and white colors.

The new generation of liquid freezer coolers takes on the predecessors with fine refinements, a new pump design, a dense fin layout, a removable top pump cover, and finally an option to regulate the speed of VRM fan, Pump, and radiator fans separately as well jointly.

This cooler is only compatible with Intel LGA1700 and 1851 sockets due to the use of a contact frame. It is also compatible with AMD AM4/AM5 sockets.

The price of this cooler is Euro 123.99 at the time of this writing.

Liquid Freezer III – 420 Specifications

ARCTIC Liquid Freezer III 420 Specs

ARCTIC is providing a 6-year warranty on this cooler and it comes with a 0.8gm tube of MX-6 thermal paste which is their top-performing thermal paste as of now.

Packing and Unboxing

ARCTIC has retained the size of the packing box from the LF-II series. However, the color scheme on the box is different. The shipping box is still in a triangle shape. I think ARCTIC should change that so that customs officials who are always in a hurry can pack the cooler back easily.

ARCTIC Liquid Freezer III 420 Box

My cooler was delivered with the packing box torn and it was not in good shape.


Let’s take a look at what is provided in the box. As I mentioned in the previous LF III 280mm AIO Review, there is no printed user manual so you need an active internet connection for the online manual.

ARCTIC Liquid Freezer III 420 Mounting Hardware

ARCTIC has supplied:

  • 1x  Set of 2x AMD Mounting Brackets
  • 1x Set of 4x AMD Black Spacers
  • 1x Set of 4x AMD Screws
  • 1x Set of 4x Intel Contact Frame Screws
  • 1x Set of 8x Philips Screws and Washers for the Radiator
  • 1x Allen Key
  • 1x tube of MX-6 thermal paste
  • 1x Intel LGA1700 Contact Frame
ARCTIC Liquid Freezer III 420 Cables 1

My major gripe with the Liquid Freezer II series of coolers was one cable connection to control the VRM fan, pump, and radiator fans. This time ARCTIC has provided two cables addressing the issue. You can use one cable to control all fans/pump using a single connector whereas you can use the other cable to control all individually.

ARCTIC Liquid Freezer III 420 Cables 2

As can be seen, there is a proprietary connector on one end that is connected to the header on the block whereas the other end has a standard 4-pin PWM connector for your motherboard.


ARCTIC Liquid Freezer III 420 Screws

I have removed the fans from the radiator to show the fan screws.

Closer Look

It is time to take a closer look at the components starting with the radiator itself.


ARCTIC Liquid Freezer III 420 Radiator 1

The 3x P14 black ARGB fans come pre-installed on the radiator. This makes the life of the user easy as you would need fewer steps to install the cooler. ARCTIC has retained the footprint of Liquid Freezer II coolers.

ARCTIC Liquid Freezer III 420 Radiator 2

Just like the predecessor, all the fans have short-length cables. ARCTIC has done cable management from the factory. There is a single PWM extension that has 3 PWM sockets to which the fans’ PWM connectors are attached. The cable going to the pump housing from the radiator passes under the sleeve of the tube.

ARCTIC Liquid Freezer III 420 Radiator 3

The radiator is made of aluminum material. The dimension of this radiator is 458x130x38mm (LxWxH). However, take note that pre-installed fans would make the overall height 65.5mm. The FPI count on this radiator is 14.

There is a 23% more surface area on these new radiators as well. The complete assembly is black and we have a 105mm gap between any two opposite end fan mounting holes. The coolant flow channel count is 12.

ARCTIC Liquid Freezer III 420 Radiator 4

Now, I am showing the tube side of the radiator. There is not much of a difference compared to the other sizes that I have tested in this generation. The connections are still almost in the center and ARCTIC has used different clamps that look quite pleasing. There is a cable coming out from the left tube. This is a  PWM cable.

ARCTIC Liquid Freezer III 420 Radiator 5

The side view of this unit is not different than what I showed on the 240mm radiator. We still have an ARCTIC branding in silver on the side frame. The rubber tubes have a length of 450mm and they have a black sleeve over them. The tube diameter is 12.4mm OD and 6mm ID.


ARCTIC has gone back to the drawing board and revamped the block design including the pump and cold plate.

ARCTIC Liquid Freezer III 420 Pump Cover 1

If you remember the 40mm VRM fan was integrated right into the block of the Liquid Freezer II series of the coolers. This is not the case here. There is a removable pump cover that has an embedded 60mm fan for VRM cooling. There are fin design-guided vanes over the top that provide air inflow for the fan.  The fan is rated for 400 to 2500 RPM using 0.05A at 12VDC. The ARGB LEDs are rated for 0.40A at 5VDC.

ARCTIC Liquid Freezer III 420 Pump cover 2

I am showing the base of the cover. Two pillars use magnetic attachment with the block. You can see 7 contact pads on the PCB right below the top. These make contact with the pins on the block.

ARCTIC Liquid Freezer III 420 Pump Cover 3

To ensure unrestricted airflow, there are large size cutouts on the frame around the embedded fan. This fan blows air towards the near socket area of the motherboard.

ARCTIC Liquid Freezer III 420 Pump Block 1

Now coming to the main area of interest which is the block itself, we can see a smart design that is in a right-angled design. There is a pump and propeller on the vertical side whereas the cold plate is on the base. Speaking of the cold plate, ARCTIC has increased the fin density on the cold plate and optimized the coolant flow channels. The pump is rated for 800 to 2800 RPM using 0.35A at 12VDC.

ARCTIC Liquid Freezer III 420 Pump Block 2

Now I am showing the PCB on the block which is also vertically mounted. There are 7 contact pins over the top that connects to the pump cover. There is a soldered interface towards the right for the integrated fan header.

ARCTIC has employed the ET8213Q controller which is a 3-phase sensor-less FOC controlled DC Brushless Motor drive IC with built-in Rdson 1 Ω drive MOS. The chip is highly integrated with the components required for motor control, requiring fewer peripheral components, low noise, and low motor torque ripple.

ARCTIC Liquid Freezer III 420 Pump Block 3

I am showing the backside of the housing. This housing encapsulates the rotary fittings and tube connection. The tubes can be slid within this housing only.

ARCTIC Liquid Freezer III 420 Pump Block 6

ARCTIC has used a copper base measuring 40x44mm which is the same size as on the LF-II coolers. But the internals of the cold plate are re-designed.

ARCTIC Liquid Freezer III 420 Pump Block 5

I am showing the side view of the fully assembled block.


ARCTIC Liquid Freezer III 420 Fan

There are three P14 PWM PST Black edition fans provided with this cooler. There are 5x blades on each fan. The backside of the fan has a spiral-shaped 4x arms assembly holding the blades assembly with the frame. These would cut the air coming through the fans and would give a spiral flow though it is not a focused flow. The fan is powered by a 4-pin PWM connector. I am not going into the details as we have done a detailed review of these and other ARCTIC fans separately.

The specifications of the fans are:

Type4-pin PWM Connector
Speed200~1700 RPM
Airflow72.80 CFM
Air Pressure2.40 mmH₂O
Bearing TypeFluid Dynamic Bearing
Input Voltage12VDC
Input Current0.12A


I am not covering the installation steps/process. Please refer to the user manual for that. But I would mention any observation during the installation. You would need to remove the Intel ILM to install contact frame on the supported Intel sockets.

I have tested this cooler on the AMD AM5 platform on GIGABYTE X670E AORUS MASTER Motherboard. The NVMe heatsink cover obstructed the block and I had to remove the NVMe heatsink cover to install this cooler.

ARCTIC has mentioned that they would provide free-of-charge NVMe heatsink to the users so you are covered. Just run it with them. But keep in mind that this is a Gen5 port that needs an active cooling solution.

You would need to put a some pressure on the mounting sides to compress the block so that it can be installed on this socket.


The following configuration is used for thermal testing:

  • AMD Ryzen 7950X
  • ARCTIC Liquid Freezer III – 420 Black
  • Kingston Renegade Fury 32GB 6400MHz CL32 DDR5 kit
  • ASRock Phantom Gaming RX 7600 Graphics Card for Display
  • Sabrent Rocket 4 Plus 2TB NVME SSD
  • Open-Air Test Bench

Here is the settings table for testing:

Clock (MHz)Auto
Voltage (V)Auto
Boost Clock Override+75Hz
Platform Thermal Throttle LimitAuto
Thermal PasteNoctua NT-H1
Thermal Paste ApplicationDots Method
Test Run Time30 minutes
Idling Time10 minutes
All Fans Speed100% PWM Duty Cycle
Pump Speed
Stress SoftwareCINEBENCH R23.2
Monitoring SoftwareHWINFO64

We are reporting delta temperature in the graph because room temperature varied from 20.9°C to 22.8°C throughout the day. The testing is done on an open air bench system. Once inside the chassis, the temperatures are expected to rise and would largely depend upon the optimal airflow inside the chassis.


ARCTIC Liquid Freezer III 420 Thermal Performance

The Liquid Freezer III 420 Black has a superb performance and it does so doing 40 dB(A) approximately which is too good. ARCTIC has managed to keep the same sound profiles by using the same fans on the new generation of the liquid coolers.


So far I have tested 240mm, 280mm, and 360mm size Liquid Freezer III series coolers. This time I have tested the 420mm flagship cooler from the new generation. This cooler has a large size aluminum radiator measuring 458x130x38mm (LxWxH). Three P14 PWM PST Black fans come pre-installed over the radiator making the overall height of 65.5mm. The FPI count is 14 and channels count is 12. The rubber tubes have black sleeves and ID/OD rating is 6.0/12.4mm.

Since I have tested the black version, there is no A-RGB lighting on this cooler. That is why there is no A-RGB cable coming out from the pump housing. Similarly the pre-installed fans have only PWM cables already daisy-chained and cable managed from the factory.

ARCTIC has provided the users the function of either controlling all fans (radiator fans, pump motor, and VRM fan) using a single cable or a cable with 3 connectors for individual control. ARCTIC has used the same P14 PWM fans that I found on the Liquid Freezer – II 420 cooler. Obviously, ARCTIC did not feel a need to revamp their fans and have used the fans from the last generation. P14 max could have been used on black only variant though.

These fans use Fluid Dynamic Bearings and are rated for up to 1700 RPM and features auto-stop function. They can produce total airflow of 72.80 CFM with a static pressure of 2.40mmH₂O. The noise level and MTTF rating are not mentioned. Each fan has a 4-pin PWM connector. The internal header on the block is not standard. The bundled fan cables use proprietary connector for that header.

The block and VRM fans have uplift. There is a removable pump cover that has 60mm embedded fan for the VRM cooling. The fan draws fresh air from the top where there are guided vanes and flows the air towards the near socket area of the motherboard. The VRM fan is rated for up to 2500RPM.

The block has a smart design which is in right angled layout. The main PCB is exposed on the vertical side and it shows that ARCTIC has used the ET8213Q controller which is a 3-phase sensor-less FOC controlled DC Brushless Motor drive IC. The PCB has 7-pin contact pins on the top that make contact with the pads on the pump cover. There is a fan header integrated into the PCB to which the bundled fan cable(s) is to be connected. ARCTIC has improved the cold plate design and has provided dense fin stack with improved coolant flow channels. The pump is rated for up to 2800RPM.

Now coming to the installation part of this cooler, this cooler is compatible with AMD AM4/AM5 and Intel LGA1700 only sockets. The total items required to install mounting brackets for the AM5 socket is 10 in 4 steps. It is convenient and I have no issue there.

On Intel, side you can only use this cooler on LGA1700/1851 sockets which is due to the fact that you would need to remove the ILM to install the contact frame for these sockets. ARCTIC could still have provided standard Intel mounting by making contact frame mounting optional in my opinion. This would have made this cooler compatible with other Intel sockets as well.

This cooler has a price tag of €123.99. This is a good price for a 420mm liquid cooler and certainly gives many coolers a run for their money provided your case can house this size cooler.

The thermal performance of this cooler is quite well. It is silent and outperforms the Liquid Freezer II and III 360s with quite some margin. This cooler has won our Performance and Value Awards.


  • Excellent Thermal Performance
  • 60mm VRM Fan
  • Removable Top Cover
  • Integrated Cable Management
  • Ability to control all fans and pump individually
  • Ability to control all fans and pump using a single cable
  • Pre-Installed Fans
  • Compatible with Intel LGA1700/1851 sockets
  • Compatible with AMD AM4/AM5 sockets
  • Improved Cold Plate and pump design
  • Easy Installation
  • Excellent Noise Output
  • 6-Year Warranty
  • Price


  • Intel Contact Frame should be optional
  • ARCTIC branding is fixed on the pump cover
  • Motherboard Compatibility
  • PC Case Compatibility
EnosTech Value Award
Enos Tech Performance Award