Evolution Phase: Arctic Cooling Accelero Twin Turbo Pro and Scythe Setsugen

These two new coolers are in fact an evolutionary twist on the old models, however, the results of this evolution are dramatically different. Read more in our review!

by Sergey Lepilov
06/15/2010 | 03:59 PM

The cooler makers often prefer to modify and enhance the already existing products. Far not every manufacturer and way not always manages to design a cooler with well-balanced cooling efficiency, acoustic characteristics and price on the first attempt. Moreover, modifying an existing product is always way cheaper than developing and launching into production a completely new model. The release of new CPUs and graphics cards works as an additional stimulus (and sometimes as a necessity) for launching new cooler revision, because they may use different mounting holes or new PCBs that are incompatible with existing cooler systems.


At the same time, it is fairly hard to consider the two new coolers, which we are going to discuss today, slightly modified products. Arctic Cooling Accelero Twin Turbo Pro and Scythe Setsugen have been altered significantly compared with their predecessors. Therefore, we believe it makes more sense to regard these products as another phase of evolution in the cooling solutions market. Well, let’s see how successful this phase turned out to be and if Accelero Twin Turbo Pro and Setsugen can cope with contemporary graphics accelerators without hurting the users’ ears too much.

Arctic Cooling Accelero Twin Turbo Pro

Package and Accessories

The Swiss Arctic Cooling Company sticks to its traditional packaging: compact clear plastic blisters molded specifically for the given cooler and its accessories. I am sure it is very affordable and besides, you can see practically the entire cooler:


There is a tag on the front of the package stating that the new Accelero Twin Turbo Pro supports such new graphics cards as Nvidia GeForce GT 240 and ATI Radeon HD 5870. The back of the package bears performance diagrams, specifications and key features, which has become traditional for Arctic Cooling.

The bundled accessories lie on a special tray inside the package:

Among them are heatsinks for the memory chips and voltage regulator components, installation manual, power adapter for the Molex connector, screws and washers, and two meshed panels for the back of the system case.

Design and Functionality

If you are familiar with the previous model – Accelero Twin Turbo, you will notice that the Pro-version is very similar to it:


However, although the new cooler maintains the same length, it became 48 mm taller and 15 mm wider. Its weight has increased from 350 to 450 g.

This product still consists of four copper heatpipes 6 mm in diameter that come out of the copper base. They hold an array of aluminum heatsink plates pressed firmly against them. There is a plastic frame with two fans sitting on top of the heatsink. Here are the detailed dimensions of the Accelero Twin Turbo Pro cooler:


It is very convenient that the manufacturer provides detailed cooler dimensions , because it will make it very easy to determine whether Accelero Twin Turbo Pro would be compatible with any of the graphics cards the potential buyers have in mind.

The heatsink has “grown” five plates bigger: now there are 35 plates in the array. The plates have also become thicker: 0.5 mm instead of 0.25-0.3 mm. The heatsink has also become denser: the gaps between the plates have been reduced from 2.5 to 2.1 mm.

So, Twin Turbo Pro now has relatively large effective heatsink surface for a VGA cooler: it equals 4080 cm2. I also have to point out to you that the heatpipes in the new cooler are now arranged in different direction: they come out of the base and head straight up and pierce the heatsink from the top towards the bottom. Before they used to come out of the base and head down and then go through the heatsink array from the bottom towards the top of the array. The new cooler will obviously have no compatibility issues with the graphics, which GPU chip is located closer to the lower edge of the PCB. I also have to add that the heatpipes are soldered to the grooves in the base plate.

The plastic frame with the fans is attached to the heatsink with two side clips:

It sits very tightly on the heatsink and is pretty hard – though possible - to remove:

Another evolutionary modification is the use of two 92 mm fans on Accelero Twin Turbo Pro instead of two 80 mm fans used before:

The rotation speed of these 11-bllade fans varies automatically depending on the graphics card load and the GPU temperature in the interval from 1000 to 2000 (±10%) RPM creating a 54 CFM airflow. The noise, which Arctic Cooling usually declares in Sones is claimed to be 0.2 ~ 0.6 Sone, which is exactly what the noise level of the previous Twin Turbo model was. The maximum fan power consumption shouldn’t exceed 3.6 W. Unfortunately, we do not know the life span of their fluid dynamic bearings.

The cooler base is covered with a rather thick layer of highly efficient Arctic Cooling MX-2 thermal interface:

The cooler base is very even, no issues here. However, the finish quality could have been better.

Compatibility and Installation Tips

Accelero Twin Turbo Pro cooler is compatible with most contemporary graphics cards. That is why there are two retention holes in every corner of the steel retention plate. Besides, Arctic Cooling engineers also made a variable steel plate that allows installing the cooler higher or lower:

Before installing Accelero Twin Turbo Pro, you have to remove the protective film from the bundled small heatsinks and stick them onto the memory chips and voltage regulator components:


You also have to remove the protective film from the corners of the steel retention plate. You will need to cover the retention holes with sticky plastic rings that will hold off the pressure and protect the graphics chip from possible damage:

And then all you need to do is tighten the cooler using screws with washers on the back of the PCB and plug the power cable into the connector on the graphics card or into a Molex adapter.

Unfortunately, we failed to install Accelero Twin Turbo Pro onto a reference Radeon HD 5850, because the lower left side of the cooler kept pushing against the aluminum casing around the output ports:

Also the cooler won’t fit onto Radeon HD 5770 and HD 5750. However, it should fit just fine onto Radeon HD 5870 listed among compatible graphics accelerators, because the GPU on this graphics card is located a little farther away from the back panel than on Radeon HD 5850. Too bad we didn’t have this particular graphics card at the time of tests, so we can’t tell you with certainty if that is the case. Let’s take the manufacturer’s word for granted this time.

However, we can assure you that Accelero Twin Turbo Pro will be installed without any issues onto a Radeon HD 4890, even if you use a Thermalright VRM2 heatsink:

The new cooler is priced at $49.90, which is exactly the same as the price of the recently reviewed Zalman VF950 LED. Arctic Cooling offers a 6-year warranty, which may, however, vary depending on the region.

Scythe Setsugen (SCVSG-1000)

Package and Accessories

The new cooler from the Japanese Scythe comes in a tall flat box with a photo of the cooler and its accessories alongside with almost all the technical info about it:


The cooler comes with a universal backplate, an aluminum heat-spreader plate for the voltage regulator components of GeForce GTX graphics cards, heatsinks for the memory chips and VRM, NVIO heatsinks, retention kits, Scythe thermal paste and a copper pad for the GPU:

Design and Functionality

It is hard to tell why, but Scythe Setsugen reminded me of Scythe Musashi. And even though the latter has a completely different concept, Setsugen can be considered evolutionary development of Musashi. Take a look at the new cooler:


Setsugen consists of a copper nickel-plated base with four copper heatpipes 6 mm in diameter coming out of it that hold four heatsink arrays with a fan sunk into their center. We remember that Zalman VF950 LED cooler has a fan sunk into the heatsink, although it hasn’t been implemented too well. Scythe Setsugen measures 180 x 33.5 x 139 mm and weighs 375 g.

Scythe Setsugen heatsink is designed with M.A.P.S. technology (Multiple Airflow Pass-through Structure), which we have already discussed before in our Scythe Mugen 2 and Kabuto reviews. Four independent heatsink arrays are connected to one another only with a few thin bridges, and the distance between the arrays measures 3 mm:

Each heatsink array contains 67 aluminum plates, each 0.3 mm thick. The plates are placed at 1.5 mm distance from one another. Two middle arrays and the corners of the external arrays are only 10 mm wide, which allowed integrating the fan into the heatsink like that. The calculated effective heatsink surface is 3350 cm2.

Note that the fan is by default installed in such a way that the airflow is driven away from the graphics card and towards the heatsink, instead of being directed towards the graphics card, as it usually is in most cases:

However, it looks like they only installed the fan like that in the very first Setsugen batches, because they started to recommend turning the fan the other way immediately after the launch and the first benchmark results, so that it could blow the air towards the graphics card sucking the air through the heatsink plates. It is true, in this case the GPU temperature under peak load turned out 3-4°C lower, and the temperature of the VRM components – 7-8°C lower.

Heatpipes are soldered to the copper nickel-plated base. It is finished perfectly:

The base plate is also impeccably even:

Now I have to say a few words about the fan used in Scythe Setsugen cooler. It is a slim SlipStream 120:


The fan is 120x120x12 mm in size that is why it could fit directly into the heatsink, instead of sitting on top of it. Its rotation speed can be adjusted using the enclosed variator on a bracket to be installed into back panel of the system case:

The fan can work at a speed ranging from 800 to 2000 (±10%) RPM. It will generate 19.4-45.47 dBA of noise and create 19.53-33.67 CFM airflow. The slide bearing used in this fan should last for 30,000 hours or more than 3.4 years in a non-stop operation mode.

Compatibility and Installation Tips

Scythe Setsugen is compatible with all graphics cards except Radeon HD 5770, HD5750 and dual-GPU graphics accelerators. The cooler is installed using special mounts inserted into the nuts that slide freely along the grooves in the base. There is also a backplate with large thumb nuts that catch on to the mounts:


Everything is very quick and easy. If the graphics processor chip appears below the protective frame you should use a copper 1.5 mm pad from the accessories bundle. Do not forget to apply a layer of thermal interface to both sides of the pad before placing it onto the chip.

This is what Scythe Setsugen looks like installed onto a Radeon HD 5850:

Obviously, about a third of the airflow from Setsugen fan and of the heat from the heatsink plates is sent directly to the CPU cooler:


Moreover, we can’t help noticing that the 120 mm cooling fan covers smaller part of the CBP than two 92 mm fans of the previously discussed Arctic Cooling Accelero Twin Turbo Pro.

Scythe Setsugen cooler is manufactured in Taiwan and is priced at $49.8. It comes with a 1-year warranty.

Technical Specifications and Recommended Pricing

Testbed and Methods

We tested the new cooling systems inside a closed system case. Our testbed was identical for all coolers throughout the test session and featured the following configuration:

To increase the total system heat dissipation and make the testing conditions a little harder for the participating cooling solutions we overclocked our quad-core processor to 4 GHz and increased its Vcore to 1.36875 V in the mainboard BIOS. The memory voltage was at 1.64 V and its frequency was around 1.55 GHz (7-7-7-14_1T timings).

The testing programs were installed under Microsoft Windows 7 Ultimate RTM x64. We used DirectX End-User Runtimes libraries (from February 2010) and Catalyst 10.3 beta and GeForce/ION Driver 196.34 beta graphics card drivers. We used 12 runs of FireFly Forest test from the semi-synthetic 3DMark 2006 suite in 2560x1600 resolution to warm up the graphics cards. We enabled anisotropic filtering 16x:

Besides, we additionally used FurMark version 1.8.0 burn test that was launched for about 20 minutes in stability test mode in 2560x1600 resolution:

We used MSI Afterburner version 1.5.1 and RivaTuner version 2.25 alpha to monitor the frequencies and temperatures of our cards.

The tests were run at least twice for each type of load. The temperature stabilization period between the two test cycles was about 10-12 minutes. The ambient temperature was checked next to the system case or open testbed with an electronic thermometer with 0.1°C precision that allows monitoring the temperature changes over the past 6 hours. During our test session room temperature stayed around 24.8-25.1°C.

The noise level of each cooler was measured after 1:00 AM in a closed room about 20 m2 big using CENTER-321 electronic noise meter. The noise level for each cooler was tested outside the system case when the only noise sources in the lab were the cooler and its fan(s). The noise meter was installed on a tripod and was always at a 150 mm distance from the cooler fan rotor. The mainboard with the graphics card equipped with the tested cooler was placed at the edge of the desk on a sheet of polyurethane foam. The lowest noise reading our noise meter device can register is 29.8 dBA and the subjectively comfortable noise level in these testing conditions was around 37 dBA (do not mix it up with low noise level). The fan(s) rotation speed was adjusted in the entire supported range using the new controller revision by changing the voltage with 0.5 V increment.

The today’s testing participants and the reference graphics card coolers were tested in three fan speed modes: automatic mode, at maximum speed and at average speed. During our test session the VRM components of the cards voltage regulators were topped with Thermalright VRM2 and VRM4 heatsinks without a fan (passive mode).

Cooling Efficiency Tests

Diamond Radeon HD 4890 1 GB XOC

Diamond Radeon HD 4890 1 GB XOC graphics card works at higher frequencies of 925/4200 MHz, so we didn’t overclock it any more:


Let’s check out the obtained results:

Unfortunately, the cooling efficiency of Scythe Setsugen leaves much to be desired. In quiet mode at 800 RPM even with a Thermalright VRM2 heatsink, the new cooler can’t provide sufficient cooling for the PCB voltage regulator components, so it is hard to imagine what could have happened if we had used the bundled aluminum heatsinks instead of the Thermalright VRM2.It is interesting that the increase in the rotation speed of the Scythe fan doesn’t help improve the situation: the temperatures drop just a little bit. In the end Setsugen cooler with its fan working at the maximum speed turned out only as good as the reference cooler of the Radeon HD 4890 in its automatic speed mode. Not that impressive, I have to say.

The efficiency of our today’s second testing participant, Arctic Cooling Accelero Twin Turbo Pro, is on the contrary very high. This cooler remained ahead of the graphics card reference cooler in all speed modes of its two fans. And as we know, the reference cooler of this graphics card is pretty efficient. Even in quiet mode at 1080 RPM the new cooler can cope with an overclocked Radeon HD 4890 burned to the utmost by the monstrous FurMark. This result is truly impressive. And the advantage of the new Arctic Cooling product over the Scythe cooler sometimes reaches 30°C!

ATI Radeon HD 5850 1 GB

For the tests with Radeon HD 5850 we took a reference ATI graphics card with nominal frequencies. To make it harder on the tested coolers we overclocked the card from 725/4000 MHz to 900/4800 MHz without changing its voltage settings:


Before getting to the primary tests, we decided to check the efficiency of VRM heatsinks from Arctic Cooling bundle. These pseudo-heatsinks were installed using default sticky tape and compared against Thermalright VRM4 paired with Scythe Setsugen cooler at 800 RPM. The load was created using 3DMark 2006 test. The results turned out quite predictable:


Even under relatively moderate load created by the Firefly test from the 3DMark 2006 testing suite, the temperature of the PCB VRM components under the default heatsinks from the Twin Turbo Pro bundle got dangerously close to 110°C, so you can take a good guess what could have happened during FurMark. At the same time, Thermalright VRM4 heatsink provided more than 30°C better thermal conditions for the VRM components than the small Arctic Cooling heatsinks. Of course, during the primary benchmarking session we tested our coolers under two types of operational load using only Thermalright VRM4 for the voltage regulator components (I have to remind you that Twin Turbo Pro is incompatible with Radeon HD 5850). Here are the obtained results:

I have to point out right away a significant difference between the load created by two fireflies in 3DMark 2006 and the load in FurMark. We didn’t see such humongous temperature difference on Radeon HD 4890 even with the weak coolers. I also have to say that Scythe Setsugen could compete against the reference Radeon HD 5850 cooler. I really wish we could compare the two today’s leaders against one another.

Acoustic Performance

The graph below shows the noise generated by the today’s testing participants compared against the noise from a reference ATI Radeon HD 5850 cooler:

I would like to add a few words of my own to the obtained results. There is nothing to say about the reference Radeon HD 5850 cooler, because it is the noisiest cooler of the today’s testing participants. Even at 1300 RPM its fan produces some crackling sounds that don’t allow us to call it acoustically comfortable. Of course, the fan won’t be able to cool the graphics card at this speed at all: not only during overclocking but also in its nominal mode.

Among the alternative VGA coolers we have to point out the noise from Scythe Setsugen fan. Unfortunately, it has left a pretty negative impression. We could only call it quiet at about 800 RPM, while at 1000-1050 RPM it creates certain dissonance with the heatsink plates and produces a very unpleasant and even annoying sound.

Unlike other testing participants, Arctic Cooling Accelero Twin Turbo Pro is an absolute leader of our acoustic tests today. This cooler is impressively quiet and has impeccably balanced fans. There are no parasitic sounds of any kind in the entire rotation speed range, and it only becomes loud after 1500 RPM. At 1100-1200 RPM it is a very quiet, unbelievably quiet cooler. Great job, AC!


Before we get to summarizing all cons and pros for the today’s testing participants, we have to stress that without proper cooling of the VRM components, Accelero Twin Turbo Pro and Setsugen can only be used on low-end and mainstream graphics accelerators, which do not require high-quality VRM heatsinks. The default aluminum heatsinks included with both coolers can only provide sufficient cooling for the appropriate components under low operational load and at nominal frequencies, which many of you are not interested in at all. It is extremely important and until cooler makers start paying due attention to this matter, all their new cooling products will remain half-finished.

Now a few words about the tested coolers. Unfortunately, Scythe Setsugen didn’t prove up to our expectations. We can only consider its cooling efficiency up to 1100 RPM fan speed, because at higher rotation speeds the noise from the cooler is too high. And at these low speeds Scythe Setsugen can only compete against even noisier reference coolers and only under low GPU loads. During the performance tests in applications like FurMark, Setsugen can’t ensure proper cooling of the GPU at all. Among its definite advantages we should point out universal design, simple installation and low price.

The product from the Swiss Arctic Cooling made a completely different impression. Accelero Twin Turbo Pro is a high-quality and true evolutionary development of the older model, when all the modifications and changes were indeed for the best. This new cooler proved very effective and quiet and will definitely satisfy even those users who care most of all about the acoustic performance of their system. Besides, Twin Turbo Pro is also very easy to install and is compatible with many contemporary graphics accelerators, which unfortunately, do not include the reference Radeon HD 5850/5770/5750. We look forward to testing the new Accelero Twin Turbo Pro revision that should be free from these issues and should offer a complex solution to the problem mentioned in the first paragraph of this review.

P.S.: As we learned while working on this review, the Japanese Scythe discontinued their Setsugen cooler and is currently preparing to launch its second version with some serious modifications and changes.