by Doors4ever
07/31/2006 | 02:44 PM
It is a system that uses some liquid as coolant; the coolant is usually water or its solutions (hence the term a water cooling system). Its main components are:
High efficiency and low noise level are the main requirements. Additionally, one may want to consider such factors as compact size, ease of installation, compatibility with modern processor types, maintenance, and exterior design.
The same as to any cooling system, but the manufacturer has to find an optimum balance between the parameters of the good liquid cooling system and the manufacturing cost. For example, a larger heatsink improves heat transfer, but this contradicts the compactness requirement; a more powerful fan would make the system noisier, etc. This is a difficult task and the developer has to agree to compromises. The market success of a liquid cooling system depends on how optimal the result is.
It may seem strange, but yes it does. Corsair, the famous manufacturer of memory modules, offers even not one but two models of liquid cooling systems: the COOL by Corsair was tested on our site (for details see our article called COOL Water-Cooling System from Corsair and Not a Word about Memory), and this article is about the Nautilus500. The Corsair Nautilus500 consists of an external unit you can put on the system case or into any other place and of a water-block that is mounted on the CPU.
The package is a little longer than a mainboard box.
The face and reverse sides of the box show you the system from the front and back. You can also learn here that the system got its name for its ability to take off and dissipate as much as 500 watts!
The photograph shows the accessories to the water-cooling system (from top to bottom and from left to right):
The external unit combines a 350lph pump, a radiator and a 120mm fan (12V, 0.3A, 1800rpm, 74.4CFM). There are no controls on the front panel, just the name of the system and a narrow slit which is highlighted at work. It is also an indicator of the On/Off status and of the level of liquid in the system.
On the top panel there is an opening for pouring liquid in and a 120mm fan under a protective grid. On the bottom panel there is a radiator and feet with soft stickers so that they didn’t scratch the surface of the system case or desk. The fan is blowing air through the radiator from bottom to top.
At the back of the unit there is a fan speed selector (it can be set at High or Low positions), a connector for power and for pump and fan speed control, and two fittings for pipes. The fittings have valves that do not allow the liquid to flow out of the system when you disassemble it.
The water-block comes with pipes already attached:
The water-block’s base is covered with film to protect it during transportation and is ideally finished. In the next photograph it like a mirror reflects a part of the plate for mounting the water-block on AMD K8 processors.
The water-block is fully made of copper and is not composite, so we don’t know much about its internal design. They only say that the water-block is made using the micro-channels technology.
It’s all very simple because the system comes to you already assembled. You can shorten the pipes if necessary. Then you insert the fittings into the pipes and secure them with clips.
Then you connect the pipes to the main unit, attach power and fill the system up. The included coolant consists of 94-96% propylene glycol, 3% water and 1-3% additives, but there’s not enough of it in the bottle to fully fill the system. You have to add some distilled water. The system takes in about 1 liter of liquid in total.
The whole assembly and installation procedure is described in the colorful illustrated manual (950KB).
Corsair puts an emphasis on how easily and quickly the water-block can be installed on different types of processors. You don’t have to take the mainboard out of the system case to do that. To mount the water-block on LGA775, insert the plastic poles into the holes around the socket:
Apply some thermal paste on the processor and place the water-block on it. Then put the spongy pad and top it with the X-shaped plate that is hitched to the poles.
The water-block is installed in a likewise manner on Socket 478 except that you don’t use the poles; the H-shaped plate is fastened to the loops in the fastening frame.
Since the water-block is fastened to the standard frame, it can be mounted on any AMD K8 processor (Socket 754, 939, 940 and AM2). You put the identically shaped protective metal plate on the spongy pad and press it down with the bracket, hitching at one side of the frame. The other part of the bracket is hitched to the other side. Then you just secure the bracket with a screw.
It looks more difficult on paper than it is in reality. All the operations are performed easily and quickly with your own hands.
Unfortunately, it is. It’s normal that the system is audible at the maximum speed of its 120mm fan (~1800rpm). In the quiet mode (~1300rpm), there is less noise, but a very unpleasant whistle appears. Increasing or decreasing the fan speed might have helped to get rid of it, but smooth speed adjustment is not implemented. As a result, I had to test the Corsair Nautilus500 at the maximum fan speed.
It depends on what you compare it with. At a clock-gen frequency of 325MHz and a core voltage of 1.55V the temperature of an AMD Athlon 64 3000+ processor (Socket AM2) overclocked to 2925MHz and running the S&M utility was only 62°C with the Nautilus500 and 68°C with the Scythe Mine cooler. So, the Corsair Nautilus500 is surely more effective than the Scythe Mine and is far better than the box coolers AMD and Intel supply with their processors. On the other hand, the Corsair Nautilus500 was beaten by the Tuniq Tower 120 cooler by 3°C (57.6°C and 54.8°C, respectively) when they were cooling a dual-core Intel Pentium D 930 overclocked to 3.98GHz without any voltage increase.
Power consumption and heat dissipation of Intel Pentium D processors is very high, especially if you overclock them, so I was wary of checking the coolers with a voltage increase, expecting errors right after the launch of the S&M test. The Corsair Nautilus500 managed to surprise me, however, as it coped with the Intel Pentium D overclocked to 4.25GHz (290MHz FSB) with the core voltage increased to 1.45V. The CPU temperature rose to 68.1°C as opposed to 65.9° with the Tuniq Tower 120. So, this liquid cooling system obviously has a highly efficient water-block that is capable of quickly taking heat away from the CPU and giving it over to the coolant. The higher temperature with the water cooler may be due to the small size of its heatsink and the low performance of the pump.
On the other hand, temperature is relative rather than an absolute parameter. Different mainboards will report different temperatures under the same conditions, which are also hard to keep the same, considering the great diversity between the tested cooling systems. A long-time test is needed, but the longer you test coolers, the higher the ambient (room) temperature grows. So, I compared the systems by the maximum achievable overclocking: the Tuniq Tower 120 kept an Intel Pentium D 930 stable at 4.43GHz clock rate (295MHz FSB) and a core voltage of 1.5V. The CPU thermal throttling was triggered when I tried the Corsair Nautilus500 under the same conditions.
The main advantage of liquid cooling systems over traditional air coolers is that they can take heat out of the system case. This is especially noticeable when a hot processor like Intel’s dual-core Pentium D is being cooled. When overclocked and put under load, it can warm up a whole room, let alone the small volume of a computer case.
Besides that, the Corsair Nautilus500 has a few specific features:
The main drawback of the Corsair Nautilus500 is its noisiness and lack of smooth fan speed adjustment. It also provides no means to cool the near-socket space on the mainboard, which is a common defect of many water-cooling systems. You have to use additional fans to cool the chipset’s heatsink and the transistors in the CPU power circuit.
The rest of the drawbacks come from the unavoidable compromises the developer had to agree to: the efficiency of the Nautilus500 is lower than that of the best air coolers on heat pipes because the heatsink is small and the pump performance is low to make the system compact and less noisy. You should also be aware that the Corsair Nautilus500 is more expensive than air coolers. Its recommended price is $159.99 US.
Besides obvious drawbacks, there are possible ones. For example, how many reinstallations will the plastic poles for mounting the water-block on LGA775 last? Will the spongy pad that ensures tight contact between the water-block and the CPU remain stiff after your using it for a while? Will the pump begin to rattle after a month or two? It’s impossible to get answers to these questions during a short test, you have to use the system for a long time to find this out. So, these are not problems proper, but you must be aware of the possibility of their arising.
You can visit the Corsair forums or ask any question on our forums.