Antec Kuhler H₂O K240 CPU Liquid Cooler Review

When it comes to the Power Supply Units, Antec needs no introduction. Antec was founded in 1986 and they have built their name with continuous innovation and quality products. But they are not confined to the boundaries of the PSUs only. They are producing the PC Chassis, cooling solutions, fans as well. Their business spans over 40 countries around the globe with their headquarter based in California.

In this content, we will be taking a look at their thermal solution for CPU based on liquid cooling. Antec Kuhler H₂O K240 is a 240mm liquid cooler for the CPU with 240mm radiator. This is not an Asetek design as the pump of this unit is integrated inside the radiator’s housing which makes the block to be of less bulky in size and weight. Antec has bundled two 120mm Blue LED fans in the parcel. They are static color fans not RGB. This cooler is compatible with almost all sockets of Intel and AMD including Intel LGA 2066 and AMD AM4 except TR4. This is the second cooler on our test bench and it is time to check its design and thermal performance.

Specifications

Packaging and Unboxing

The cooler is shipped inside a colorful packaging based on a cardboard box. A picture of the unit is printed on the front side of the box along with the brand name and logo. Antec’s seal of Quiet Computing is pasted here as well. Some of the features are highlighted at the bottom. The back side of the box has Antec’s brand name and logo printed on it along with the model of the unit. It is printed here that unit is environmentally friendly and safe as well as anti-corrosive. Specifications of the cooler are printed in 8 languages on the other side. A serial no sticker is pasted as well on the bottom. The top side of the box has Antec brand name printed on the top left side. Kuhler H₂O K240 is printed right next to the picture of the unit. Antec is offering 3 years of warranty on this cooler. The left side of the box has Antec’s brand name and model of the unit printed on it. The right side of the box has the same layout as is on the left side. When we opened the box, there was a Styrofoam pad placed on the top of all. Removing the pad shows the content of the parcel well placed inside an egg box with every item and accessory enclosed inside transparent container/sheet.

Contents

As is the case with the majority of the coolers, Antec has included complete mounting hardware for AMD and Intel sockets as well as fan mounting on the radiator. List is:

  • 1x AMD Bracket
  • 1x Intel Bracket
  • 1x Intel Backplate
  • 2x 120mm Fans with washers and screws
  • 4x Intel LGA-2011 Screws
  • 4x Knurled Nuts
  • 4x Knurled Nuts
  • 4x Screws
  • 1x Transit Line

Closer Look

The Antec Kuhler H₂O K240 is CPU liquid cooler which is a 240mm cooling solution. This is not an Asetek design as the pump is not housed inside the block unit but it is integrated inside the radiator housing. This is definitely a different design approach which will remove the vibration element from the block and move it to the radiator itself. The radiator itself is a slim design without rounded corners. It is made of aluminum material. This is typical AIO implementation that we see in the market with only copper element coming on the base of the CPU block and radiator made of aluminum. The Fins Per Inch count is 17 and it seems like a dense fin stack for which high static pressure fans would be ideal. The dimension of the radiator is 288x120x27mm (LxWxH) With 25mm fan the total height of the unit when ready will be 52mm. Mounting holes have a spacing of 110mm. There is no protective sheet under the mounting holes above the fins which is why pay attention when mounting fans on the radiator. The top side has Antec branding printed in the white color which looks pleasant. As described above, the pump has been integrated inside the radiator housing which is why we see the back chamber/block to be of a rather larger in size when it comes to the radiators on most of the AIOs in the market. The dimension of the chamber where the pump is integrated is 32x120x30mm (LxWxH). There is a 0.28mm wall sitting between the pump and radiator’s fin stack point of contact. To power the pump, there is a 470mm SATA cable which is to be connected to the SATA power connector coming from the PSU. There is no 3-pin cable to read or control the speed of the pump. In this particular design, the pump will always operate at 100% of its rated speed. The water pressure rating of the pump is 1m ± 0.2m. The flow rate is 1.5L per minute. Lifespan is 50000 hours at 25°C room ambient with 15~65% RH. The noise level is rated at ≤36 dB(A). There is a note on the backside of the chamber with pump, informing the user to clean the unit in time. Antec is using Teflon Coating Tubing which is expected to last up to 15 years. This is according to the Antec’s testing. The tubes have a dimension of 8x10x350mm where 350mm is the length of the tubing. The tubes are nylon sleeved. The tubes are bit rigid but nothing major. The tubes are securely connected to the barbs to prevent leakage.

As mentioned above the pump is on the radiator, hence the block has less weight on it as compared to the units with an integrated pump on the blocks. The block is made of the plastic material and is in black color. There is a circular raised surface on the top side of the block. This is the holder place for the Intel bracket. The block has a dimension of 50x58x20mm. The base of the block is made of the copper. Thermal paste comes pre-applied on to the base. We removed the thermal paste before taking pictures hence it is not visible there. The thermal paste is using the polymer materials. There is a silver color Antec branding pasted on top of the block for a pleasant look. The letter c was coming off the surface and is sharp. The tubes are connected to the rear side of the block in 90° fitting. The In and Out are clearly marked indicating which tube is taking hot liquid to the radiator and which tube is bringing the liquid inside the block.

There are two 120mm fans bundled in this cooler. These fans have 120x120x25mm where 25mm is the height or thickness of the fan. These fans don’t have RGB lighting but a single blue color. These fans are rated at 900~1800±10% RPM. The noise level is rated between 20~30 dB(A). The airflow is rated at 73.31 CFM. The lifespan of these fans is rated at 40000 hrs at 25°C room ambient with 15~65% RH. These are PWM fans with 4-pin connector. The length of the power cable is 285mm. Antec has provided a Y cable which they refer to as transient line, to connect two fans on a single header and control them from a single header. The length of this cable is 297mm+100mm. These fans are using the full ceramic bearings with the ceramic shaft for increased durability.

There are 9 blades in each fan which are translucent in brown color. There is Antec brand name printed on the center. There is a white color frosted ring above the frame in a circular direction. The ring has blue color LEDs in it which illuminates the complete ring to create a sublime look. The frame has low height on the middle edges which is understandable as rings are given unobtrusive access. There are white color anti-vibration pads on the mounting corners. There is a 4-arms assembly holding the motor and blade section. The frame has more thickness on the edges to accommodate the ring. A sticker is pasted on the center with Antec branding on it. The fans’ power cables are braided.

Installation

The cooler has been tested on the Intel LGA-2011(3) socket. Here are the steps that you would need to follow for this socket:

  • Install the fans on the radiator using the supplied screws.
  • Install the LGA-2011 screws from the labeled container in the accessory bag.
  • Place the Intel bracket on the top side of the block such that it fits in securely around the circular raised surface.
  • Apply thermal paste on the top surface of the CPU.
  • Place the block on the CPU by aligning the mounting holes on the Intel bracket with the LGA-2011 screws.
  • Take out the 4x Knurled Nuts of size M3*12 and one by one start screwing them on the LGA-2011 screws. Go diagonally for even pressure.
  • Connect the fans’ power cables to the Y cable provided in the accessory bag.
  • Connect the y cable to the PWM fan header on your motherboard, preferably the CPU fan header.
  • Connect the SATA cable of the pump to the SATA power cable coming from the PSU.

This will complete the installation. The beauty of the AIO is that it gives better clearance to the DIMM slots and first PCIe slot and better compatibility to the RAM height and chassis. Such was the case with this cooler as well.

Testing Methodology

Our test bench setup consists of:

  • Asus Rampage V Edition 10
  • Intel i7 6850k
  • Crucial Ballixtics Elite 4x4GB @ 3000MHz
  • Gigabyte GTX 1060 6GB
  • Samsung 840 EVO 250GB SSD
  • WD Black 6TB
  • Corsair AX1200i

Following software were used for the testing and monitoring.

  • Asus Real Bench v 2.44
  • Real Temp GT v 3.70

We are using Noctua NT-H1 thermal paste to reduce the thermal effect that may come with the pre-applied or supplied thermal paste. This is to ensure the standard testing for all the coolers on the same hardware. Since the testing is done in an uncontrolled environment, we are using the delta temperatures on our graphs. The cooler is tested on stock clocks i.e 3.6GHz using 1.136V manual VCore. The Asus RealBench 2.44 is used to stress test the cooler’s performance. Fans were set to run at their 100% RPM and water pump seems to be running at 100% at all times as we don’t have control over its speed. CPU is overclocked to 4.3GHz with 1.350V manual Vcore. The stress test is run again. Average of the test run is calculated. The max temps on each core are summed up and divided by the core count to give the average figure. Delta temp is calculated by subtracting the ambient temperature from the average temperature. No rounding is done on the ambient temperature.

Results

On 3.6GHz, the cooler was idling at 2.1°C and 25.91°C was the temperature under load which is 0.09°C below the Corsair H100i V2. This is a negligible difference and as such both coolers were at par in terms of thermal performance. Needless to say that both 240mm coolers were trailing behind the NZXT Kraken X62 which is 280mm cooler.

On 4.3GHz, the cooler was idling at 2.83°C and 42.17°C was the temperature under load which is 1.01°C above the Corsair H100i V2. The performance margin of both 240mm coolers was approximately 1°C which does not make much of a difference. Both coolers were trailing behind the NZXT Kraken X62 which is 280mm cooler.

It is summer season here and there are certain ambient noises beyond our control hence we are not measuring the sound level of the fans. Based on our experience with the fans and coolers testing, the cooler was near to silent level.

Conclusion

The Antec Kuhler H₂O K240 CPU liquid cooler is a 240mm All-In-One cooling solution from their Kuhler series of the coolers. Given the price of the cooler, this particular unit has more value written on its face than anything else. We don’t get to see any styling or feature rich functions that have much to do with aesthetic than the performance but Antec has not skipped on the performance aspect and this unit is very well catering for the needs of the budget users in the market, looking for affordable yet reliable cooling solution. Don’t worry, as two blue LED color fans are included to make this cooler look lively. This cooler is compatible with almost all Intel sockets including LGA-2066, and AMD sockets including AM4 but excluding TR4.

This cooler has 240mm radiator measuring 288x120x27mm (LxWxH). When the fans are installed on the radiator the ready unit has a height of 52mm in total. This is not an Asetek design as the pump has been integrated into the housing of the radiator. The pump is powered by the SATA connector. Unfortunately, there is no 3-pin cable coming out of the pump which can be used to monitor and control the speed of the pump so we are assuming that pump is running at 100% speed all the times. The edges of the radiator are not rounded and give better looks in this way. The chamber where the pump is integrated has a dimension of 32x120x30mm (LxWxH). There is a 0.28mm wall separating the chamber from the fin stack with built-in water channel cutouts. The water pressure rating of the pump is 1m ± 0.2m. The flow rate is 1.5L per minute. The lifespan is 50000 hours at 25°C room ambient with 15~65% RH. The pump is rated at ≤36 dB(A) noise level. Antec is using Teflon Coating Tubing which is sleeved. The tubes have a dimension of 8x10x350mm. The unit has a copper base on the block and it comes with a pre-applied thermal paste made of polymer material.

Antec has bundled two 120mm Blue LED fans with this cooler. The dimension of the fans is 120x120x25mm. These fans are rated at 900~1800±10% RPM. Their noise level is rated between 20~30 dB(A). Their airflow is rated at 73.31 CFM. The lifespan of these fans is rated at 40000 hrs at 25°C room ambient with 15~65% RH. These are PWM fans with 4-pin connector. Antec has provided a Y cable to connect two fans on a single header for controlling them off a fan header. These fans are using the full ceramic bearings with the ceramic shaft. Antec is providing 3 years of warranty on this cooler.

This cooler is rated at £61.10 at the time of the review. This is too good a price to beat for a 240mm cooler. We put the cooler with tasking of cooling the Intel i7 6850k at 3.6GHz using 1.140V and 4.3GHz at 1.350V. This is a 140W TDP chip and with overclocking the power consumption would increase. The cooler manages to come almost at similar performance level as is on the Corsair H100i V2. To be honest, there is almost similar performance margin among the 240mm coolers and this cooler fits in that well. This is the VALUE that one could have asked for.

With Antec Kuhler H₂O K240 liquid CPU cooler, Antec has created a true value for the users in terms of performance and price. This cooler has a simple design which is complemented by the addition of two Blue LED color fans to make the appearance stylish. Antec means business with their Kuhler H₂O K240 CPU Liquid Cooler and this cooler comes recommended by us for the budget users.

Antec Kuhler H₂O K240 Review

Quality
Design
Performance
Features

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I am a tech reviewer who loves to play with the hardware and do an in-depth analysis of the hardware for the content creation. I have over 120 contents to my credit and this number is ever growing. Besides, I love to assemble PCs and do troubleshooting.

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