SilverStone SST-AR01 CPU Cooler Heatsink Review

By Tom Jaskulka

Manufacturer: SilverStone Technology, Co., Ltd.
Product Name: Argon Series Heatsink
Model Number: SST-AR01
UPC: 844761009960
Price As Tested: $33.99 (Amazon | NewEgg)

Full Disclosure: The product sample used in this article has been provided by SilverStone.

SilverStone may be known for their cooling, but not necessarily their CPU coolers. As a company, they’ve brought forward many innovations and unique, successful approaches to the ATX case standard with their AP series fans and rotated motherboard enclosures. It’s not that SilverStone is a stranger to CPU cooling – there were the Nitrogen special-application series before the new Argon series, as well as the Heligon high-performance line of heat-sinks. The Argon AR01, AR02, and AR03 are all designed to be more accessible alternatives for enthusiasts, with each model fulfilling a specific purpose. The SilverStone SST-AR01 is designed to be a price/performance leader in the market, and is the cooler that Benchmark Reviews will be taking a look at today.

Looking closer at the AR01, the build quality and attention to detail started to shine through. This isn’t a cheap heatsink, no matter how inexpensive it is.

While it isn’t a deciding factor (too many others come into play when you’re talking the transfer of heat from one object to another), I was pleasantly surprised to see a near-mirror finish on the base of the AR01. Many times the direct-contact heatpipes are ground to a flat surface, leaving grooves from whatever tool was used for surfacing. It looks like SilverStone took the extra step to polish up the contact surface a bit, which all else being equal should result in better temperatures than a rough surface.

The back-plate is simple, and indeed looks quite similar (as does the mounting system) to a couple Xigmatek tower coolers I’ve worked with. It is reversible to accommodate the major sockets (AM3+/FM2, LGA1155/56/50) and the mounting kit also accommodates those sockets that use the motherboard’s built in back-plate. This photo is on an AM3+ ATX motherboard, so you should have enough clearance no matter what socket you use. Of course, some mini-ITX motherboards can result in some clearance issues, so make sure to double check clearances if you can.

Speaking of clearances, the AR-01 clears the first DIMM on a M5A990FX PRO 2.0 at least, and should on most ATX motherboards. MicroATX formats tend to crowd the socket a little more, but with low-profile memory modules becoming more popular you shouldn’t run into many clearance issues with the AR-01.

It bears repeating here that no heat-sink will work effectively unless it transfers heat from the CPU. To do that, it needs to be in contact with the CPU heat spreader or die, with the greater the contact surface the greater the potential for heat transfer. One of our own writers here at Benchmark Reviews has done a lot of work in this area, and it is certainly worth the time it takes to read (and re-read) the discoveries he made during the famous 80+ thermal paste tests (I still see Newegg reviews reference the discoveries made therein).

I mention this because I still see this as a major source of misinformation – most end users will use far too much thermal interface material when switching CPU coolers. Possibly through little fault of their own – I’ve read official repair manuals stating to use the entire tube of thermal paste when replacing a CPU and heat-sink. This is, in almost every case, FAR too much – to the point of being harmful in most cases. So do yourself a favor and get acquainted with CPU Cooler Preparations and Thermal Paste Application.

Processor and CPU cooler surfaces are not perfectly smooth and flat surfaces, and although some surfaces appear polished to the naked eye, under a microscope the imperfections become clearly visible. As a result, when two objects are pressed together, contact is only made between a finite number of points separated by relatively large gaps. Since the actual contact area is reduced by these gaps, they create additional resistance for the transfer of thermal energy (heat). The gasses/fluids filling these gaps may largely influence the total heat flow across the surface, and then have an adverse affect on cooling performance as a result.

The only reason for using Thermal Interface Material is to compensate for flaws in the surface and a lack of high-pressure contact between heat source and cooler, so the sections above are more critical to good performance than the application of TIM itself. This section offers a condensed version of our Best Thermal Paste Application Methods article.

After publishing our Thermal Interface Material articles, many enthusiasts argued that by spreading out the TIM with a latex glove (or finger cover) was not the best way to distribute the interface material. Most answers from both the professional reviewer industry as well as enthusiast community claim that you should use a single drop “about the size of a pea”. If there was ever any real advice that applies to every situation, it would be that thermal paste isn’t meant to separate the two surfaces but rather fill the microscopic pits where metal to metal contact isn’t possible.

After discussing this topic with real industry experts who are much more informed of the process, they offered some specific advice that didn’t appear to be a “one size fits all” answer:

1. CPU Cooling products which operate below the ambient room temperature (some Peltier and Thermo-electric coolers for example) should not use silicon-based materials because condensation may occur and accelerate compound separation.
2. All “white” style TIM’s exhibit compound breakdown over time due to their thin viscosity and ceramic base (usually beryllium oxide, aluminum nitride and oxide, zinc oxide, and silicon dioxide). These interface materials should not be used from older “stale” stock without first mixing the material very well.
3. Thicker carbon and metal-based (usually aluminum-oxide) TIM’s may benefit from several thermal cycles to establish a “cure” period which allows expanding and contracting surfaces to smooth out any inconsistencies and further level the material.

The more we researched this subject, the more we discovered that because there are so many different cooling solutions on the market it becomes impossible to give generalized advice to specific situations. Despite this, there is one single principle that holds true in every condition: Under perfect conditions the contact surfaces between the processor and cooler would be perfectly flat and not contain any microscopic pits, which would allow direct contact of metal on metal without any need for Thermal Interface Material. But since we don’t have perfectly flat surfaces, Thermal Material must fill the tiny imperfections. Still, there’s one rule to recognize: less is more.

CPU coolers primarily depend on two heat transfer methods: conduction and convection. This being the case, we’ll concentrate our attention towards the topic of conduction as it relates to the mating surfaces between a heat source (the processor) and cooler. Because of their density, metals are the best conductors of thermal energy. As density decreases so does conduction, which relegates fluids to be naturally less conductive. So ideally the less fluid between metals, the better heat will transfer between them. Even less conductive than fluid is air, which then also means that you want even less of this between surfaces than fluid. Ultimately, the perfectly flat and well-polished surface is going to be preferred over the rougher and less even surface which required more TIM (fluid) to fill the gaps.

This is important to keep in mind, as the mounting surface of your average processor is relatively flat and smooth but not perfect. Even more important is the surface of your particular CPU cooler, which might range from a polished mirror finish to the absurdly rough or the more complex (such as Heat-Pipe Direct Touch). Surfaces with a mirror finish can always be shined up a little brighter, and rough surfaces can be wet-sanded (lapped) down smooth and later polished, but Heat-pipe Direct Touch coolers require some extra attention.

To sum up this topic of surface finish and its impact on cooling, science teaches us that a smooth flat mating surface is the most ideal for CPU coolers. It is critically important to remove the presence of air from between the surfaces, and that using only enough Thermal Interface Material to fill-in the rough surface pits is going to provide the best results. In a perfect environment, your processor would mate together with the cooler and compress metal on metal with no thermal paste at all; but we don’t live in perfect world and current manufacturing technology cannot provide for this ideal environment.

Probably one of the most overlooked and disregarded factors involved with properly mounting the cooler onto any processor is the amount of contact pressure applied between the mating surfaces. Compression will often times reduce the amount of thermal compound needed between the cooler and processor, and allow a much larger metal to metal contact area which is more efficient than having fluid weaken the thermal conductance. The greater the contact pressure between elements, the better it will conduct thermal (heat) energy.

Unfortunately, it is often times not possible to get optimal pressure onto the CPU simply because of poor mounting designs used by the cooler manufacturers. Most enthusiasts shriek at the thought of using the push-pin style clips found on Intel’s stock thermal cooling solutions. Although this mounting system is acceptable for casually-used computers, there is still plenty of room for improvement when overclocking.

Generally speaking, you do not want an excessive amount of pressure onto the processor as damage may result. In some cases, such as Heat-pipe Direct Touch technology, the exposed copper rod has been pressed into the metal mounting base and then leveled flat by a grinder. Because of the copper rod walls are made considerably thinner by this process, using a bolt-through mounting system could actually cause heat-pipe rod warping. Improper installation not withstanding, it is more ideal to have a very strong mounting system such as those which use a back plate behind the motherboard and a spring-loaded fastening system for tightening.

Heat-pipe technology uses several methods to wick the cooling liquid away from the cold condensing end and return back towards the heated evaporative end. Sintered heatpipe rods help overcome Earth’s gravitational pull and can return most fluid to its source, but the directional orientation of heatpipe rods can make a significant difference to overall cooling performance.

The following is retained word for word from the source article, but note that not every CPU cooler will be or can be tested in a horizontal orientation. Please refer to the testing methodology on the next page or the pictures in the article to see how each specific cooler was tested.

For the purpose of this article, all CPU-coolers have been orientated horizontally so that heatpipes span from front-to-rear with fans exhausting upward and not top-to-bottom with fans blowing towards the rear of the computer case. This removes some of the gravitational climb necessary for heatpipe fluid working to return to the heatsink base. In one example, the horizontally-mounted tower heatsink cooled to a temperature 3° better than when it was positioned vertically. While this difference may not be considered impressive to some, hardcore performance enthusiasts will want to use every technique available to reach the highest overclock possible.

The CPU coolers were tested installed in a computer case in its normal orientation (a NZXT H630). A 200mm top/rear exhaust fan was added to the enclosure to aid in cooling VRMs and most of the front drive cages were removed to clear the path from the 200mm intake fan. The GPU remained installed during testing. All fans were set to 100% to remove that variable from the results (motherboard fan control was disabled). This is how I would assume most enthusiasts would set up a similar case while overclocking a similar platform.

All tests were performed using the AIDA64 Extreme Edition Stability test, using 100% fan settings on an Asus M5A99FX PRO R2.0 (PWM/motherboard fan controls were disabled for testing). The test was allowed to run until temperatures plateaued, then I recorded the ambient temperature of the intake air and began logging temperatures over the next minute. After an initial warm-up run, I ran each test at least three times (more if I received inconsistent results), and recorded the ambient temperature again. Once I had “good data,” I dropped the best and worst results and subtracted the (average over the test) ambient temperature from the median result to arrive at the delta T temperature you see in the chart.

Each time a heat-sink was swapped, the Tuniq TX-2 thermal interface material I used for each application was cleaned off of the contact surfaces with Arctic Silver’s ArctiClean two-step TIM remover, and an appropriate amount of TX-2 replaced for the next heat-sink. Due to the nature of applying TIM and mating two surfaces, I would like to adopt a 3% margin of error – even though my thermometers and the built-in thermal diode measure temperatures down to one-tenth of a degree Celsius, it could be assumed that temperatures within a degree of each other are essentially the same result.

• Motherboard: Asus M5A99FX-PRO R2.0 w/ 1708 BIOS/UEFI
• System Memory: 8GB (2x4GB) GSkill Ares 1600MHz DDR3 CL8
• Processor: AMD FX-8320 Piledriver, 4.6GHz 1.38V/1.428V w/LLC on Extreme
• Audio: On-Board
• Video: Sapphire Radeon 7950 3GB 1000MHz Core, 1300MHz mem
• Disk Drive 1: OCZ Vertex 2 240GB
• Enclosure: NZXT H630, +200mm exhaust fan (top/rear)
• PSU: Rosewill Lightning 800W Modular 80+ Gold
• Monitor: 1920×1080 120Hz
• Operating System: Windows 7 Ultimate 64-bit w/SP1
• Motherboard Settings: LLC set to Extreme, Turbo disabled, HPC on, only CPU Mulitplier changed, 1.38V/1.428V (LLC)

There’s a couple things to keep in mind while dissecting the data in the chart above. First, the approximate load that each cooler had to dissipate was about 200W from the CPU (during the stability test, my P3 Kill-A-Watt measured around 290W at the wall, approximately 110W at idle). This is a relatively heavy load for most CPU coolers, so you won’t be able to compare these results to most Intel platforms (they would generally consume less power under load). Because of this high-heat load, you may see some coolers performing differently than they would on an alternate platform.

These are all relatively high-end coolers, ranging in price from $35 to $140. The AR01 comes in at the low end, at $34.99. While it finished at the bottom of this chart, keep in mind this cooler was designed as a quiet alternative for lower heat loads. What these results should tell you is that you should really look at spending at least $70 if you want good results with a hot CPU like an overclocked FX-8320. Still, the AR01 kept the 4.6GHz 8320 under its thermal limit, in a worst-case scenario – not a bad showing for the price.

Well, it didn’t manage to de-throne the Cooler Master EVO…or did it? Even though it was a degree or two warmer, I can’t really say it was a poor performer. An overclocked FX-8320 is something to be reckoned with as far as thermal loads are concerned, and this type of cooler just isn’t designed for that. It almost seemed like the heat-pipes and fins became saturated with heat, and just couldn’t bleed it off fast enough. A little more mass might do it…but that’s what the AR03 is for. For what it’s worth, I added an additional fan in a push/pull arrangement, and that managed to bring down the temps another degree and a half or so (normally, I don’t include every fan arrangement in the results – most of the time adding a fan only results in a drop of one degree Celsius or less, which is usually not worth the cost and increase in noise). It seems a push/pull arrangement was a little more beneficial for the AR01 than most coolers, which leads me to believe it would perform well under less demanding loads as it just had trouble shedding the 200 watts of heat.

If anything, the AR01 serves to show how important it is to choose a cooler that is appropriate for your platform. You can’t expect miracles out of even the best products.

Thankfully, the AR01 still puts in a strong showing – the fact it kept an FX-8320 pumping out 200W of heat under its thermal limit shows that it will perform in a worst-case scenario. I would expect it to perform even better on an 1155 or 1150 socket. Besides, if you want more performance, there are other options in the Argon line. For the price, the AR01 performed as expected.

While some may not like the color scheme, the heat-sink itself is attractively finished and nicely polished. There isn’t much to 120mm tower coolers, but SilverStone manages to extract a premium look out of their base-level AR01.

Similarly, the AR01 is constructed at or above the level of other coolers in its price range. I was surprised to see the contact surface of the heat-pipes polished to a near-mirror finish, which is unusual it seems for coolers that cost twice as much.

At the end of the day, the AR01 performs its function adequately. It’ll keep an FX CPU cool, so it should keep almost every other CPU cool as well. The installation was comparable to other products, and the fan mounting system was the best I’ve had a chance to work with.

Remember, this heatsink retails online for $33.99 (Amazon | NewEgg). That’s a decent price for a CPU cooler that is easy to install, relatively quiet under operation, and keeps your CPU cooler than the stock fan and heat-sink. It won’t keep up with the high-end coolers, but it isn’t designed to.

I wouldn’t have a problem recommending this cooler to anyone that was looking for an inexpensive, well built and quiet cooler. We may have to chat about their expectations (you won’t hit 5 GHz with this, or any other $35 cooler) but it will keep most systems running cool and quiet. There are other popular options in this price range but I appreciated some of the changes SilverStone made to the 120mm tower cooler formula, enough to prefer working with the AR01.

+ Wonderful fan mounting system + Good quality throughout + Small changes add up + Easy to work with + Performs as expected for the price + The small touches to reduce noise seem to work

– Hopefully you like blue! – Heat-sink mount does not allow multiple orientations (at least on AMD platforms)

• Performance: 7.50
• Appearance: 9.00
• Construction: 9.50
• Functionality: 8.00
• Value: 8.50

Recommended: Benchmark Reviews Seal of Approval.

COMMENT QUESTION: What is your favorite CPU cooler heatsink?