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[nextpage title=”Introduction”]

The Kühler H₂O 620 is a sealed liquid CPU cooling system from Antec. Let’s test it and check its performance.

The Kühler H₂O 620 is actually manufactured by Asetek, which also makes watercoolers for Corsair- such as the H70; which we already reviewed. Even though the Kühler H₂O 620 resembles the Corsair H50, they are not exactly the same product.

The product box is large and has no openings. See Figure 1.

Figure 1: Package

Figure 2 illustrates what is inside the box: a premounted and sealed block-pump-hoses-radiator system, a 120 mm fan, manual, and installation hardware.

Figure 2: Accessories

In Figure 3, you can see the Antec Kühler H₂O 620.

Figure 3: The Kühler H₂O 620

This watercooler is discussed in detail in the following pages.

[nextpage title=”The Kühler H2O 620″]

Figure 4 shows the CPU block into which the pump is integrated.

Figure 4: CPU block

Figure 5 reveals base of the block. It is made of copper and comes with thermal compound applied. Note the two cables on the block: one must be connected to the motherboard in order to power the system; the other one powers the radiator fan- so that the circuitry at the block can control the speed of the fan.

Figure 5: Base

In Figures 6 and 7 you see the radiator, which must be installed at a 120 mm fan opening at the rear of the case.

Figure 6: Radiator

Figure 7: Top view

In Figure 8 is the 120 mm fan that comes with the H₂O 620. Its cable is short because it is not intended to be connected to the motherboard but to the block wire, as we already mentioned.

Figure 8: Fan

[nextpage title=”Installation”]

In Figure 9, you see the clip used to install the Kühler H₂O 620 on Intel CPUs. The AMD clip is very similar to this one. The backplate shown at the right goes on the solder side of the motherboard, and the metal frame at the left goes on the component side and holds the block.

Figure 9: Intel clip

Figure 10 shows the mounting system in place. This frame supports sockets 775, 1155, 1156, and 1366 CPUs.

Figure 10: Intel frame installed

In Figure 11, the Kühler H₂O 620 is installed in our computer. Note that the fan is placed between the radiator and the case rear panel, so a second fan can be installed at the other side of the radiator.

Figure 11: Installed in our system

[nextpage title=”How We Tested”]

We tested the cooler with a Core i7-860 CPU (quad-core, 2.8 GHz), which is a socket LGA1156 processor with a 95 W TDP (Thermal Design Power). In order to get higher thermal dissipation, we overclocked it to 3.3 GHz (150 MHz base clock and 22x multiplier), keeping the standard core voltage (Vcore), which was the maximum stable overclock we could make with the stock cooler. Keep in mind that we could have raised the CPU clock more, but to include the stock cooler in our comparison, we needed to use this moderate overclock.

We measured noise and temperature with the CPU idle and under full load. In order to get 100% CPU usage in all threads, 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 the Intel stock cooler with a copper base (included with the CPU), as well as with other coolers. Note that in the past, we tested coolers with a socket LGA775 CPU, and we retested some "old" coolers with this new methodology. This means you can find different values in older reviews than the values you will read in the next page. Every cooler was tested with the thermal compound that accompanies it.

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 left panel of the case was open.

The sound pressure level (SPL) was measured with a digital noise meter, with its sensor placed 4" (10 cm) from the fan. We turned off the case and video board cooler fans so they wouldn’t interfere with the results. 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 isn’t the case here.

Hardware Configuration

• Processor: Core i7-860
• Motherboard: Gigabyte P55A-UD6
• Memory: 2 GB Markvision (DDR3-1333/PC3-10700 with 9-9-9-22 timings), configured at 1,200 MHz
• Hard disk: Seagate Barracuda XT 2 TB
• Video card: Zotac GeForce GTS 250
• Video resolution: 1680×1050
• Video monitor: Samsung Syncmaster 2232BW Plus
• Power supply: Seventeam ST-550P-AM
• Case: 3RSystem L-1100 T.REX Cool

Operating System Configuration

• Windows 7 Home Premium 64 bit

Software Used

• Prime95
• SpeedFan

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 all coolers listed below. Each measurement was taken with the CPU at idle and at full load. In the models with a fan supporting PWM, the motherboard controlled the fan speed according to core load and temperature. On coolers with an integrated fan controller, the fan was set at the minimum speed on the idle test and at full speed on the full load test.

		Idle Processor			Processor at Full Load
Cooler	Room Temp.	Noise	Speed	Core Temp.	Noise	Speed	Core Temp.
Intel stock (socket LGA1156)	14 °C	44 dBA	1700 rpm	46 °C	54 dBA	2500 rpm	90 °C
Cooler Master Hyper TX3 G1	14 °C	47 dBA	2050 rpm	33 °C	56 dBA	2900 rpm	62 °C
Zalman CNPS10X Extreme	14 °C	45 dBA	1400 rpm	27 °C	53 dBA	1950 rpm	51 °C
Thermaltake Silent 1156	14 °C	44 dBA	1200 rpm	38 °C	49 dBA	1750 rpm	69 °C
Noctua NH-D14	14 °C	49 dBA	1250 rpm	27 °C	49 dBA	1250 rpm	53 °C
Zalman CNPS10X Performa	14 °C	46 dBA	1500 rpm	28 °C	52 dBA	1950 rpm	54 °C
Prolimatech Megahalems	14 °C	40 dBA	750 rpm	27 °C	60 dBA	2550 rpm	50 °C
Thermaltake Frio	14 °C	46 dBA	1450 rpm	27 °C	60 dBA	2500 rpm	50 °C
Prolimatech Samuel 17	14 °C	40 dBA	750 rpm	40 °C	60 dBA	2550 rpm	63 °C
Zalman CNPS8000A	18 °C	43 dBA	1400 rpm	39 °C	54 dBA	2500 rpm	70 °C
Spire TherMax Eclipse II	14 °C	55 dBA	2200 rpm	28 °C	55 dBA	2200 rpm	53 °C
Scythe Ninja3	17 °C	39 dBA	700 rpm	32 °C	55 dBA	1800 rpm	57 °C
Corsair A50	18 °C	52 dBA	1900 rpm	33 °C	52 dBA	1900 rpm	60 °C
Thermaltake Jing	18 °C	44 dBA	850 rpm	34 °C	49 dBA	1300 rpm	60 °C
GlacialTech Alaska	18 °C	43 dBA	1150 rpm	36 °C	51 dBA	1600 rpm	60 °C
Deepcool Gamer Storm	18 °C	43 dBA	1100 rpm	35 °C	48 dBA	1600 rpm	62 °C
Corsair A70	26 °C	56 dBA	1900 rpm	40 °C	56 dBA	1900 rpm	65 °C
Deepcool Ice Blade Pro	23 °C	45 dBA	1200 rpm	38 °C	52 dBA	1500 rpm	64 °C
AC Freezer 7 Pro Rev. 2	23 °C	47 dBA	1750 rpm	44 °C	51 dBA	2100 rpm	77 °C
Corsair H70	27 °C	60 dBA	1900 rpm	37 °C	60 dBA	1900 rpm	61 °C
Zalman CNPS9900 Max	27 °C	55 dBA	1600 rpm	38 °C	58 dBA	1750 rpm	63 °C
Arctic Cooling Freezer 11 LP	25 °C	45 dBA	1700 rpm	51 °C	49 dBA	1950 rpm	91 °C
CoolIT Vantage	26 °C	60 dBA	2500 rpm	37 °C	60 dBA	2500 rpm	62 °C
Deepcool Ice Matrix 600	25 °C	46 dBA	1100 rpm	41 °C	53 dBA	1300 rpm	69 °C
Titan Hati	26 °C	46 dBA	1500 rpm	40 °C	57 dBA	2450 rpm	68 °C
Arctic Cooling Freezer 13	27 °C	49 dBA	1950 rpm	41 °C	53 dBA	2300 rpm	70 °C
Noctua NH-C14	26 °C	52 dBA	1300 rpm	37 °C	52 dBA	1300 rpm	61 °C
Intel XTS100H	26 °C	49 dBA	1200 rpm	42 °C	64 dBA	2600 rpm	68 °C
Zalman CNPS5X SZ	23 °C	52 dBA	2250 rpm	38 °C	57 dBA	2950 rpm	69 °C
Thermaltake SlimX3	21 °C	50 dBA	2700 rpm	46 °C	50 dBA	2750 rpm	99 °C
Cooler Master Hyper 101	21 °C	50 dBA	2600 rpm	38 °C	57 dBA	3300 rpm	71 °C
Antec Kühler H2O 620	19 °C	52 dBA	1400 rpm	34 °C	55 dBA	1400 rpm	58 °C

In the graph below, at full load 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.

 

[nextpage title=”Main Specifications”]

The main features of the Antec Kühler H₂O 620 watercooler include:

• Application: Sockets 775, 1155, 1156, 1366, AM3, AM2+, and AM2 processors
• Fins: Aluminum
• Base: Copper
• Heat-pipes: None
• Fan: 120 mm
• Nominal fan speed: 2,000 rpm
• Fan air flow: 81.3 cfm
• Maximum power consumption: Not informed
• Nominal noise level: Not informed
• Weight: 1.5 lbs (700 g)
• More information: https://www.antec.com
• Average price in the US*: USD 80.00

* Researched at Newegg.com on the day we published this review.[nextpage title=”Conclusions”]

The Antec Kühler H₂O 620 seemed to be an excellent watercooling system at first sight. It is easy to install, is elegant, and quiet; and it cooled our CPU reasonably well. However, the problem is that you don’t buy a watercooler system to cool your processor "reasonably well". When you buy a watercooler, you are looking for some extra cooling, and this product doesn’t provide it.

So, if you are looking for a watercooler just to know your computer isn’t an ordinary air-cooled one, you can buy the Antec Kühler H₂O 620; it is a good product that will not give you headaches. But if you are looking for a good cost/benefit ratio, just forget about it and look for a good air cooler.