[nextpage title=”Introduction”]
The Cooler Master Nepton 240M is a high-end liquid cooling system for CPUs. It has a 240 mm radiator with two 120 mm fans. Let’s see how it performs.
As with any sealed liquid cooling system, the Nepton 240M comes with the coolant liquid pre-filled inside the loop (block, radiator, pump, and hoses).
Figure 1 shows the box of the Cooler Master Nepton 240M.

Cooler Master Nepton 240MFigure 1: package

Figure 2 shows the contents of the box: the radiator-block set, two fans, manual, a Y harness to connect both fans to the motherboard, a small syringe of thermal compound, and the installation hardware.

Cooler Master Nepton 240MFigure 2: accessories

This water cooler is discussed in detail in the following pages.
[nextpage title=”The product”]
The sealed radiator-block system is shown in Figure 3. At the left is the radiator, which transfers heat from the circulating liquid to the air, and, at the right, is the block that transfers heat from the CPU to the coolant liquid.
The rubber hoses are 14” (358 mm) long and have 0.3” (8 mm) of diameter.

Cooler Master Nepton 240MFigure 3: sealed system

Figures 4 and 5 reveal the radiator of the Cooler Master Nepton 240M. It supports two 120 mm fan at each side and it is 1.1” (28 mm) thick.

Cooler Master Nepton 240MFigure 4: radiator

Cooler Master Nepton 240MFigure 5: radiator

[nextpage title=”The product (Cont’d)”]
Figure 6 shows the top of the block, where the pump that makes the liquid to flow is integrated. It has a cable with a three-pin connector, which must be connected to the motherboard in order to power the system. The manufacturer logo lights when the pump is powered on.

Cooler Master Nepton 240MFigure 6: block

The base of the block, which is made of copper, is revealed in Figure 7.

Cooler Master Nepton 240MFigure 7: base

Figure 8 illustrates the two “Silencio FP 120” PWM fans that come with the Cooler Master Nepton 240M (120 mm, 2,400 rpm, 1.92 W, 76 cfm, 27 dBA).

Cooler Master Nepton 240MFigure 8: fans

[nextpage title=”Installation”]
The installation of the Cooler Master Nepton 240M is simple. You must attach to the block the holders according to your CPU and, except for the LGA2011 and LGA2011-v3 CPUs, install the screws at the backplate.
Figure 9 shows the backplate and AMD holders.

Cooler Master Nepton 240MFigure 9: backplate and holders for AMD system

Figure 10 shows the base of the block with the holders for Intel CPUs installed.

Cooler Master Nepton 240MFigure 10: Intel holders installed

The last step is to install the radiator and the fans at the top panel of your case, and secure the block over the CPU. We installed the fans outside, blowing outwards.

Cooler Master Nepton 240MFigure 11: installation concluded

[nextpage title=”How We Tested”]
We tested the cooler with a Core i7-5960X CPU (eight-core, 3.0 GHz), which is a socket LGA21011-v3 processor with a 140 W TDP (Thermal Design Power). In order to get even higher thermal dissipation, we overclocked it to 3.5 GHz (100 MHz base clock and x35 multiplier), with standard core voltage (Vcore).
We measured noise and temperature with the CPU under full load. In order to get 100% CPU usage in all cores, we ran Prime 95 25.11 with the “In-place Large FFTs” option. (In this version, the software uses all available threads.)
We compared the tested cooler to other similar products. We tested each cooler with the fans at maximum speed and at “silent” mode.
Room temperature measurements were taken with a digital thermometer. The core temperature was read with the SpeedFan program (available from the CPU thermal sensors), using an arithmetic average of the core temperature readings.
During the tests, the side panels of the computer case were closed.
The sound pressure level (SPL) was measured with a digital noise meter, with its sensor placed near the top of the case. This measurement is only for comparison purposes, because a precise SPL measurement needs to be made inside an acoustically insulated room with no other noise sources, which is not the case here.
Hardware configuration

Operating System Configuration

  • Windows 7 Home Premium 64 bit SP1

Software Used

Error Margin
We adopted a 2°C error margin, meaning temperature differences below 2°C are considered irrelevant.
[nextpage title=”Our Tests”]
The table below presents the results of our measurements. We repeated the same test on each cooler listed below, with the CPU at full load. On the model with software speed control, the fan speed was set on the control software that comes with the cooler, while on the other ones the fan speed was adjusted in the motherboard setup.
As we are comparing the temperature difference between the CPU and the air outside the computer (and not the actual CPU temperatures), there is no bias in taking measures under different room temperatures. Both heat transfer physics and our practical tests proved this.

Cooler Room Temp. Noise Speed Core Temp. Temp. Diff.
Thermaltake Water 2.0 Extreme (maximum) 17 °C 55 dBA 1,950 rpm 58 °C 41 °C
Thermaltake Water 2.0 Extreme (minimum) 17 °C 44 dBA 1,250 rpm 60 °C 43 °C
Thermaltake Water 3.0 Ultimate (maximum) 17 °C 56 dBA 1,900 rpm 41 °C 24 °C
Thermaltake Water 3.0 Ultimate (minimum) 17 °C 43 dBA 1,050 rpm 48 °C 31 °C
Corsair H100i GTX (maximum) 9 °C 59 dBA 2,600 rpm 34C 25 °C
Corsair H100i GTX (minimum) 9 °C 41 dBA 1,000 rpm 53 °C 44 °C
Cooler Master Nepton 240M (maximum) 13 °C 49 dBA 2300 rpm 39 °C 26 °C
Cooler Master Nepton 240M (minimum) 13 °C 39 dBA 900 rpm 58 °C 45 °C

In the graph below, you can see how many degrees Celsius hotter the CPU core is than the air outside the case. The lower this difference, the better is the performance of the cooler.

Cooler Master Nepton 240M

In the graph below, you can see how many decibels of noise each cooler makes.

Cooler Master Nepton 240M

[nextpage title=”Main Specifications”]
The main specifications for the Cooler Master Nepton 240M CPU cooler include:

  • Application: Sockets AM2(+), AM3(+), FM1, FM2(+), LGA 1150, LGA1155, LGA1156, LGA1366, LGA2011-v3, and LGA2011
  • Radiator dimensions: 10.8 x 4.7 x 1.1 inches (274 x 119 x 27 mm) (W x L x H)
  • Block height: 1.9 inches (49.1 mm)
  • Fins: Aluminum
  • Base: Copper
  • Heat-pipes: None
  • Fans: Two, 120 mm
  • Nominal fan speed: 2,400 rpm
  • Fan air flow: 76 cfm
  • Power consumption: 2 x 1.92 W
  • Nominal noise level: 27 dBA
  • More information: https://www.coolermaster.com/
  • MSRP in the U.S.: USD 112.00

[nextpage title=”Conclusions”]
At first sight, the Cooler Master Nepton 240M seems to be a “common” liquid cooling system, with no highlights like the huge radiator of the Thermaltake Water 3.0 Ultimate or the software control system of the Corsair H100i GTX.
However, our tests proved that the Cooler Master Nepton 240M can deliver a performance that is on par with these two watercoolers (who had the best performance on our tests to date.) Besides that, it achieved that performance with a lower maximum noise level, and it also costs less.
So, we can say the Cooler Master Nepton 240M is a liquid cooling system that combines excellent cooling performance and cost/benefit ration, deserving our Golden Award.