[nextpage title=”Introduction”]
The Corsair H45 CPU is a low-end liquid cooling system. It has a 120 mm radiator with one 120 mm fans. Let’s see how well it performs.
As with any sealed liquid cooling system, the Corsair H45 comes with the coolant liquid pre-filled inside the loop (block, radiator, pump, and hoses).
Figure 1 shows the box of the H45.

Corsair H45Figure 1: package

Figure 2 shows the contents of the box: the radiator-block set with fan installed, manual, a spacer (to use between your case panel and the radiator in case it doesn’t fit), and the installation hardware.

Corsair H45Figure 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 block, that transfers heat from the CPU to the coolant liquid and, at the right, the radiator, which transfers heat from the circulating liquid to the air.
The rubber hoses are 11” (280 mm) long and have 0.4” (10 mm) of diameter.

Corsair H45Figure 3: sealed system

Figures 4 and 5 reveal the radiator of the Corsair H45. It comes with one 120 mm fan installed and it is 1.1” (28 mm) thick. The fan model is DF121225SM from Dynaeon, with 2,300 rpm, 5.4 W, 94 cfm and 31 dBA.
An interesting detail of the H45 is that the pump (which makes the fluid flow inside the system) is integrated to the radiator, and not to the block as seen in the majority of similar products. So, there are two power cables here: one four-pin for the fan, and one three-pin for the pump.

Corsair H45Figure 4: radiator

Corsair H45Figure 5: radiator

Figure 6 shows the top of the block. As we mentioned before, the pump is not located no the top of the block like on most systems, but on the radiator. Because of this, the block is very flat, being only 0.9″ (22 mm) tall.

Corsair H45Figure 6: block

The base of the block, which is made of copper, is revealed in Figure 7. The thermal compound comes preapplied.

Corsair H45Figure 7: base

[nextpage title=”Installation”]
The installation of the Corsair H45 is simple. On Intel LGA1151, LGA1150 or LGA1155 CPUs, just install the backplate that comes with the cooler on the solder side of the motherboard (on AMD and LGA2011/LGA2011v3 Intel CPUs you use the original motherboard backplate), put the correct frame over the block and attach it using four spring-loaded screws, as shown in Figure 8.

Corsair H45Figure 8: Intel frame installed

The last step is to attach the radiator to the fan.

Corsair H45Figure 9: installation finished

[nextpage title=”How We Tested”]
We tested the cooler with a Core i7-6950X CPU (ten-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 3.8 GHz (100 MHz base clock and x38 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 cooling systems we had at the time. We tested each cooler with the fans controlled automatically by the motherboard.
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.
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 10 Home 64 bit

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.
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 3.0 Ultimate 21 °C 46 dBA 1200 rpm 55 °C 34 °C
Corsair H100i GTX 22 °C 52 dBA 2050 rpm 58 °C 39 °C
Thermaltake Frio Extreme 19 °C 49 dBA 1450 rpm 56 °C 35 °C
SilverStone AR01 21 °C 46 dBA 1900 rpm 65 °C 44 °C
Corsair H45 21 °C 53 dBA 2000 rpm 59 °C 38 °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.

Corsair H45

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

Corsair H45

[nextpage title=”Main Specifications”]
The main specifications for the Corsair H45 CPU cooler include:

  • Application: sockets AM2(+), AM3(+), FM1, FM2(+), LGA 1150, LGA1155, LGA1156, LGA1366, LGA2011-v3, and LGA2011
  • Radiator dimensions: 6.6 x 4.7 x 1.1 inches (168 x 119 x 28 mm) (W x L x H)
  • Block height: 0.9 inches (22 mm)
  • Fins: aluminum
  • Base: copper
  • Heat-pipes: none
  • Fans: one, 120 mm
  • Nominal fan speed: 2,300 rpm
  • Fan air flow: 94 cfm
  • Power consumption: 5.4 W
  • Nominal noise level: 31 dBA
  • More information: https://www.coolermaster.com/
  • MSRP in the U.S.: USD 60.00

[nextpage title=”Conclusions”]
The Corsair H45 is an interesting liquid cooling system. It is simple to install and inexpensive, being a good alternative to the heavy high-end air coolers.
The H45 surprised us regarding to its performance: it performed well compared to two of the best air coolers we tested so far, but also wasn’t bad compared to the best liquid cooling systems we included in this comparison.
On the other hand, the price it pays for such a cooling performance was the high noise level, caused by its high speed fan.
So, the Corsair H45 is a good entry-level watercooler, with good cost/performance ratio, if you don’t mind about a noisy PC.