The Cooler Master Nepton 280L has won many awards due to its advanced design, special manufacturing process, and outstanding performance. What’s left now is to get rid of the exaggerated noise of the JetFlo 140 as we’ve seen in our Cooler Master Nepton 140XL review. After the long wait, Cooler Master has announced the new and improved Nepton 120XL and 240M with a new exclusive design that provides higher efficiency and lower noise levels compared to the existing Nepton(s).
We have the Cooler Master Nepton 240M arrived in our lab for today’s review, courtesy of Cooler Master Malaysia. It’s pretty obvious that the Nepton 240M is made to replace the Seidon 240M, but will it stand up to the fierce competition of self-contained liquid coolers?
(The Cooler Master Nepton 240M is retailed at RM389)

CPU Socket
Intel 2011-3 / 2011 / 1366 / 1150 /
1156 / 1155 / 775
AMD FM2 / FM2+ / FM1 / AM3+ / AM3 / AM2+
75 x 69.8 x 49.1 mm (3 x 2.7 x 1.9
Radiator Dimensions
274 x 119 x 27 mm (10.8 x 4.7 x 1 in)
Radiator Material
Fan Dimensions
120 x 120 x 25 mm (4.9 x 4.9 x 1
Fan Speed
800~2400 RPM (PWM) ± 10%
Fan Air Flow
16.5 – 76 CFM (28 – 128 m3/h) ± 10%
Fan Air Pressure
0.48~4.8 mmH2O
Fan Life Expectancy
160,000 hours
Fan Noise Level
6.5~27 dBA
Fan Bearing Type
Loop Dynamic Bearing (LDB)
Fan Connector
Fan Rated Voltage
12 VDC
Pump Life Expectancy
70,000 hours
Pump Noise Level
< 15 dBA
Pump Rated Voltage
Pump Power Consumption

Aside of the 5 year warranty badge, the packaging of the Nepton 240M emphasizes on cooling performance with an illustration of the actual 240mm radiator and the newly included Silencio FP 120 PWM fan. 

A brief description of the features of the Nepton 240M can be found at the back of the box.


The accessories included are as below:

  • 1 x Warranty information 
  • 1 x User’s Gude
  • 1 x Intel mounting kit
  • 1 x AMD mounting kit
  • 1 x Y splitter fan adapter
  • 1 x Rubber gasket 
  • 1 x Thermal paste
  • 2 x Silencio FP 120 PWM fan
A closer look at the Silencio FP 120 PWM fan, it featured 5 large fan blades specially designed for high air pressure and silent performance. This is the very same Silencio FP 120 fan from the Cooler Master Silencio 652S Silent Tower, announced back in March 2014.

The cable comse sleeved and powers up via a 4-pin fan header.

And we’re now with the main unit of the Nepton 240M, the powerful pump with it’s 240mm radiator. 

The radiator has the product name printed on it, a rather premium look we’d say.

Unlike the stiff FEP tubing found on CoolIT made self-contained liquid coolers, Cooler Master went for a pair of FEP tubes with larger diameter that is much easier to bend but kink-free.

The sealed cap, it is possible to replace the coolant but it is not advised to do so.

Here’s why – any action to tamper or remove the seal will void your warranty.

The aluminum fins on the 240mm radiator to dissipate heat from the liquid inside the loop.

This appears to be the very same pump from the existing Nepton(s), featuring long life-span up to  70,000 hours and excellent water flow up to 120 Litre per hour.

Below the pump is the copper plate to transfer heat from your CPU to the liquid that passes through the micro channels in the copper plate. Cooler Master claimed that they’ve made the skived fin area to be around 4.5 times larger than what their competitor can offer to the end users.

The included rubber gasket is supposed to be placed in between the radiator and fans to absorb vibration to achieve near silent operation.

This is a good feature that hasn’t been implemented by many renowned brand, thumb screws for fan mounting. 

The mounting kit is very simple and straightforward, all we needed to do behind the motherboard is to secure the screws with the included plastic clips to its designated socket size and place it at the back of the motherboard where the processor is.

Upon placing the backplate at the right position, secure the screws with the included stand offs – this can be done easily by hand.

The final step is to secure the pump firmly and you’re good to go. The installation process was easy but it’ll be even easier if thumb screws were used as mounting screws for the pump.

Performance Test

Test Bench Configuration
CPU Cooler
Cooler Master Nepton 240M
Intel Core i7 4770k
Graphics Card
Corsair Vengeance Pro 4GB x 2
Primary Hard Drive
Intel 520 Series 240GB
Power Supply
SilverStone Strider Plus 600W
Vector Bench Case

We fired up a CPU stress test with Prime95 with the option ‘In-place large FFTs’ for maximum heat output, under room temperature of 28ºC. We’ve also included results for various CPU coolers that we’ve tested with the same configuration as a comparison for the Cooler Master Nepton 240M.

It turns out that the Nepton 240M performed the best among the high end coolers we’ve tested, peaking only at 66°C for an Intel i7 4770K overclocked to 4.4GHz. Beating both Corsair H100i and Corsair H100 in the category of 240mm self-contained liquid coolers. This is quite an achievement, but beating the Noctua NH-D15 is really something as there aren’t many self-contained liquid coolers is even able to perform as good as the NH-D15.

Our Verdict 

Performance wise, we’re totally over the moon with what the Cooler Master Nepton 240M is capable of. While the pump itself has been a great performer, the main wow factor was the fact the Silencio FP 120 PWM fans with its jaw dropping near silent operation, we’ve never expected it to be this quiet at first glance. 
Installation was fairly easy, especially for the fans with the thumb screws. The whole process takes less than 5 minutes as majority of the parts doesn’t require tools; securing the pump and bracket however, does require a screw driver. 
Paying RM389 for the Cooler Master Nepton 240M is a worthy investment as it’s probably the best self-contained liquid cooler to date that is much cheaper than majority of self-contained liquid cooler of its category.
  • Outstanding performance 
  • Reasonably good value for money
  • Easy to install
  • The Silencio FP 120 PWM fans stays quiet even at full speed

  • There’s option to replace the coolant, but doing so will void the warranty