Antec KÜHLER H₂O 920 Review

1. Introduction2. Antec KÜHLER H₂O 920 Liquid Cooler3. Installing the Antec KÜHLER H₂O 9204. ChillControl V Software5. Performance Testing6. Acoustics Performance7. Closing Thoughts8. View All Pages

Corsair made ‘all in one' liquid cooling popular a few years ago and today the market is literally saturated with new ‘updated' versions based on the same theme. KitGuru reviewed the Antec Kühler H20 620 in March, and it earned our highest award for the combination of class leading performance and competitive pricing. The latest 920 version is a more substantial design, with dual fans and an improved radiator.

There are no shortage of processor coolers, and for those enthusiast users looking for ultimate levels of overclocking with minimal noise levels, then liquid cooling is certainly a viable option.

Antec have built a good reputation over the years for their great chassis designs and power supplies, but their recent partnership with Asetek has opened up another market – performance CPU cooling.

Kühler H2O 920 Specifications

• CPU Socket Compatibility: Intel LGA 775, 1155, 1156, 1366, AMD AM2, AM3, AM2+, AM3+
• Low profile pump ensures exceptional liquid circulation while preserving internal airflow
• Easy-bend tubes for maximum flexibility in radiator positioning
• Intelligent noise / speed control fans for quiet, efficient cooling
• Latest generation copper cold plate for optimal conduction
• Cooling Liquid – Safe, environmentally-friendly, anti-corrosive
• Fan Speed: 700 – 2400 RPM
• Fan noise (per fan): 46dBa
• Airflow (combined): 110CFM
• Tubing Length: 330 mm
• Radiator Dimensions: 151 mm (H) x 120 mm (W) x 49 mm (D)
• Cold plate/pump height: 29mm
• Fan Dimensions: 120 mm x 25 mm
• Net Weight: 0.7 kg

The Antec KÜHLER H₂O 920 is shipped in an attractively designed box which follows the Antec company colour scheme, with a nicely presented image of the cooler on the front.

Inside, the cooler is shipped in a protective box, neatly separated. There is a pump and radiator assembly. two 120mm fans, installation manual and mounting brackets and screws.

The Antec KÜHLER H₂O 920 is supplied with both mounting brackets for AMD and Intel platforms, as well as colour coded front mounted retention holders. The manual is a little hard to follow, especially as it is printed in black and white and makes no mention of colour. AMD are green, and Intel are blue, just to clarify.

The Antec KÜHLER H₂O 920 looks very like the 620 version we reviewed before, but the radiator section is much thicker.

Above left, the 620, with 120mm fan mounted is about the same width as the 920 radiator without fans. Above right, both 620 with single fan, and 920 with dual fans, attached.

There are two power cables coming from the 920, which support both 120mm fans (supplied). Above right, both fans hooked into the 920. A single 3 pin header connects to the motherboard to control the fans. Although the 920 also is supplied with a USB cable – this is needed for the interface control via the proprietary Windows software.

The Antec KÜHLER H₂O 920 mounting system is an Asetek standard design. There is a thin metal retaining ring with notches which is attached to a back plate by four screws. The pump has notches on the edges and after this is locked into position, underneath the retaining bracket, the screws are tightened to hold it in place. This is an identical mounting system to the 620. Both are interchangeable. We will delve into this in more detail shortly.

The Antec KÜHLER H₂O 920 hoses connecting the pump to the radiator are thicker, soft rubber hoses rather than the smaller, stiff hoses normally associated with other coolers in this class. The finish and build quality is excellent and the shipping gives a high level of protection for the radiator which was perfect when we took it out of the box. Often we get little ‘nicks’ and bends in the radiator array due to rough shipping and inadequate protection.

The hoses are soft and flexible and are about 13 inches long, making them about 2 inches longer than other coolers with a similar design. They are really easy to work with and the hoses are thicker than previous H70 hoses, expanded in size from 8.7mm to 10.8mm, meaning more liquid can flow through them.

The Antec KÜHLER H₂O 920 head is branded with the company and product name, and the contact head ships with a layer of quality  thermal material preapplied. The pump has an extra three pin connector to control the coolers fan, and the swivel mounts and hoses are larger than others we have seen on Asetek sourced coolers. The cooler head has thermal material pre applied.

Many would expect Antec to be using a standard four pin connector for PWM control but Antec are using a simple 3 pin head which we would assume contains wires for power and grounding.

Spot the difference: The Antec KÜHLER H₂O 620 and 920 side by side.

Today for installation, we are highlighting images showing the installation on a Gigabyte X58 Assassin motherboard and Asus Rampage III Black Edition.

The Assassin motherboard is one of the finest products we have reviewed this year, and is a worthy partner for a liquid cooling system, especially as the overclocking options are so comprehensive and detailed.

The adhesive backplate is attached without problem and four metal bolts are passed through to the front of the board. There are a possible twelve positions as can be seen in the images above. This is to cater for various slot sizes.

As we are using an Intel 1366 motherboard, the blue offset clips are used with the retaining mount system, as seen above. This retaining ring should be left in a loose position so the main cooling head can be inserted under it and then rotated into a locking position. This is a very similar method to the Corsair H50 and H70 coolers of yesteryear. It is a little fiddly, but doesn't really cause any issues.

This fan is then attached into the 120mm location. Antec recommend the fan is locked into an exhaust position so warm air is expelled from within, keeping the traditional air flow mechanic in place. As some of you may remember, Corsair wanted the H50 and H70 fans to be mounted in an intake position, therefore pulling in cool air over the radiator. The idea was fine in theory, but we didn't think it worked well within the typical airflow of a normal chassis design.

When the radiator is fixed then the cooling head can be twisted into position underneath the retention block. When completed, then the four screws can be tightened to maintain good clamping pressure.

Installation took about 15 minutes the first time, but would take less on subsequent reinstalls.

The Antec KÜHLER H₂O 920 is the first CPU cooler we have seen to be supplied with its own driver and Windows software. The Coolit Vantage would be the closest, but it was all controlled by the unit itself inside the system, rather than via software.

This has the upside of being fully configurable from the comfort of your chair, rather than having to open the case everytime you want to change a setting.

The negative point is that you are limited to using a Windows Operating System. There is no documentation supplied with the 920 so it is just as well the interface is pretty much bulletproof. For those wondering, yes it also works on 64 bit operating systems without a hitch.

The ChillControl V software is based around a very stylish and clean interface with four submenus. Dashboard, Graphs, Fan Control and Settings. The dashboard, as seen above, groups together all relevant information such as liquid temperatures, fan and pump speed and even estimated sound levels, linked to the speeds. It is worth pointing out that liquid temperature does NOT mean CPU temperature. Top right is a little interface area for preconfigured options.

Setting the preset to ‘extreme' mode, puts both fans into turbo mode, and the noise levels are pretty much unbearable with the fans spinning up from a modest 660 rpm, to an ear pounding 2,640rpm. This setting means that the fans run at full speed, even if the CPU is idling.

The graph section shows an overview of the liquid temperature in relation to the fan speeds. This can be adjusted to suit.

ChillControl V has a ‘fan control' section which allows the user to adjust the fan speed, in accordance with the liquid temperatures. You can access these by using the ‘custom' setting top right. In here, you can also adjust the alert system for high liquid temperatures or fan failure. There is no audible alarm system in place, but there are popup options in windows when the settings are breached.

The last area is the settings panel which allows adjustments of how the temperature is displayed (to suit US/UK users) and to configure the logging system. You can also change the colour of the Antec logo, which glows on the main pump unit. You can set it to 65,536 different colours, so we can't claim that this isn't well supported. Of course it is only really worthwhile if you have a windowed case.

Today we are using the latest Intel Core i7 990x Extreme Edition processor which we reviewed a short while ago. This is the current mainstream flagship processor from Intel.

While we could use an open test bench, we like to try and mirror more ‘realistic’ conditions, so we have built the system inside an Antec Twelve Hundred chassis. Room ambient temperatures are maintained at a steady 20c throughout testing. We use diodes to measure core temperatures.

Intel System:
Processor: Intel Core i7 980x
Motherboard: Gigabyte X58 Assassin
Thermal Paste: Noctua NT H1
Power Supply: Corsair TX850W
Chassis: Antec Twelve Hundred
Memory: GSkill RipJaws DDR3 2000mhz 6GB 7-8-7
Graphics Card: Sapphire HD5670 Ultimate Edition

Comparison coolers:
Antec KÜHLER H₂O 620
Corsair H50
Corsair H70
Coolit ECO A.L.C.
Coolit Vantage A.L.C.
Noctua NH D14

All other coolers were set to their default fan speeds for this section of the review. We used Noctua NT H1 thermal material on all coolers, as it is higher quality than any of the supplied paste. We used a custom setting on the 920 with the system kicking into high performance when liquid temperatures reached 45c.

Testing these coolers at reference voltage and speeds does not highlight the ultimate performance, but it gives us a good reference point to start from.

We are overclocking the Intel 990x to 5ghz on this board with the core voltage set to 1.5, extremely high levels and a quick way to judge ultimate overclocked cooling performance.

The Antec KÜHLER H₂O 920 manages to outperform the H70 at high settings by almost a full degree. Very close indeed, and still around a single degree behind the Noctua NH D14 cooler.

Recently we have changed our method of measuring noise levels. Ambient noise in the room is around 20dBa. We measure from a distance of around 1 meter from the chassis and 4 foot from the ground with our Extech digital sound level meter to mirror a real world situation.

KitGuru noise guide
10dBA – Normal Breathing/Rustling Leaves
20-25dBA – Whisper
30dBA – High Quality Computer fan
40dBA – A Bubbling Brook, or a Refridgerator
50dBA – Normal Conversation
60dBA – Laughter
70dBA – Vacuum Cleaner or Hairdryer
80dBA – City Traffic or a Garbage Disposal
90dBA – Motorcycle or Lawnmower
100dBA – MP3 player at maximum output
110dBA – Orchestra
120dBA – Front row rock concert/Jet Engine
130dBA – Threshold of Pain
140dBA – Military Jet takeoff/Gunshot (close range)
160dBA – Instant Perforation of eardrum

With both fans cranked to the extreme setting, we measured around 47 dBa from the 920, which is much louder than the 620. To be fair however, the 920 is generally much quieter than this, especially if you take time to configure a custom fan/liquid profile. The scores above are strictly a worst case scenario and quite often the cooler would be emitting between 32 and 36 dBa of noise.

Asetek have had great success in working with enthusiast companies such as Corsair and lately Antec. With this new range however Asetek don't list any of the specifications on their website. There is no information on pump flow rate, but with the thicker tubes it is no doubt improved on the older versions.

While many of the specifications are in question what is not in question is the performance of the Antec KÜHLER H₂O 920, it is almost on a par with the Noctua NH D14, rating less than a single degree behind it. This is an exceptional result and ideal for people who want a hassle free installation but the highest levels of processor overclocking with cooling performance. We aren't huge fans of the mounting bracket system, but it works fine once you get used to it.

How does it compare with the industry leading Noctua NH D14 cooler? As we have seen, the performance levels are close and the benefits with the 920 are that memory slots are easily accessible after a system build. There is also more room for airflow across the top of the motherboard area. It is a much tidier system build and won't cause any subsequent hardware fitting issues.

Negatively, the 920 in full performance mode is painfully loud and would only be bearable for those with hearing problems. That said, it is a worst case scenario, and even with our 990x at 4.8-5ghz, it didn't often go into full performance mode, only with PRIME loading or after 15 minutes of continually looping Cinebench. Generally it is much quieter than this and we know a lesser processor wouldn't heat the liquid as much as our 990x with 1.5 volts.

We really like the Antec ChillControl software, it is both useful and practical, although a little education is in order as the liquid temperatures recorded by this program can be often 30c lower than the CPU core temperatures.

There is no doubting this cooler will make its way into many performance systems, because unless you opt for the significantly larger Noctua NH D14 it is currently in a (mainstream) class of its own.

The Antec KÜHLER H₂O 920, costs around £75 inc vat in the UK, around £5 more than the Noctua NH D14.

Pros:

• great cooling performance
• tidy build leaves CPU socket and surrounding area free for access
• dual fan system is better than single
• good build quality

Cons:

• the mounting system is a little fiddly
• can get loud, especially without customisation
• price means it has a lot of competition

KitGuru says: High performance liquid cooler which is very well put together.

Become a Patron!