The enemy of both stability and longevity, heat changes the characteristics of silicon in a way that eventually makes it unsuitable for use in a logic circuit. Heat damage can sneak up on overclockers quickly, such as the 59 degree Celsius stability limit we encountered when overclocking AMD’s Phenom II. Similarly, many of our Core 2 Duos responded unfavorably to temperatures over 65 degrees Celsius.
But hasn’t all that changed with the advent of Lynnfield, a core that can just withstand temperatures of up to 100 degrees Celsius? We have, after all, been flirting with 95 degrees Celsius regularly while testing the overclocking capabilities of motherboards, yet still reach stable clock speeds of over 4.3 GHz.
Although our Core i7-870 sample raised the temperature level at which we had to put on the brakes, its temperature limit coinciding with our cooling and voltage limits happened by mere coincidence. Surely a platform that operates so close to its thermal limit on an open test bench would be unsuitable for use in a closed case, since the higher ambient temperatures would cause thermal throttling (Intel’s automatic speed reduction) at anything close to full CPU load. Liquid cooling could help, but recent tests have shown that anything less than a dual-fan radiator version often provides unsatisfactory results. Most users don't want to bother with a high-end liquid configuration, and most cases don’t support those enormous radiators. For the sake of builders, it’s time for us to track down the best possible air-cooling solution.

While most of today’s cooler competitors already include the necessary LGA 1156 mounting hardware, two require additional components. Sunbeamtech’s accessory mounting brackets cost around $10, while Xigamtek’s $8 universal LGA adapter is expected to eventually replace the dual-compatibility part included in current samples.
| LGA 1156 CPU Cooler Features | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Top Height | Base Height | DIMM Intrusion | Number of Fans | Fan Size | PWM Control | LGA 1156 | LGA 1366 | LGA 775 | AM3 / AM2 | |
| Arctic Cooling Freezer 7 Pro R2 | 131mm | 28mm | 12mm | One | 92mm | Yes | ✓ | ✓ | ✓ | ✓ |
| Cooler Master Hyper 212 Plus | 160mm | 38mm | 6mm | One | 120mm | Yes | ✓ | ✓ | ✓ | ✓ |
| Noctua NH-D14 | 160mm | 46mm | 42mm* | Two | 120mm, 140mm | No | ✓ | ✓ | ✓ | ✓ |
| Scythe Mugen-2 Rev. B | 156mm | 41mm | 28mm | One | 120mm | Yes | ✓ | ✓ | ✓ | ✓ |
| Sunbeamtech Core-Contact Freezer | 156mm | 38mm | 10mm | One | 120mm | No | x | x | ✓ | ✓ |
| Thermalright MUX-120 | 161mm | 47mm | 2mm | One | 120mm | No | ✓ | x | x | x |
| Thermaltake Frio | 162mm | 28mm | 11mm | Two | 120mm | No | ✓ | ✓ | ✓ | ✓ |
| Tuniq Tower 120 Extreme | 156mm | 47mm | 9mm | One | 120mm | No | ✓ | ✓ | ✓ | ✓ |
| Xigmatek Thor's Hammer | 160mm | 44mm | 24mm | Two | 120mm | No | x | ✓ | ✓ | ✓ |
| Zalman CNPS10X Quiet | 160mm | 37mm | 8mm | One | 120mm | No | ✓ | ✓ | ✓ | ✓ |
Top height in the chart above refers to the amount of mounting space needed to install the cooler in a case. Base height refers to component clearance space under the bottom fins, a number required to determine whether large coolers will fit over various motherboard sinks. DIMM intrusion refers to how far the sink extends beyond the front edge of the 3.75”-wide silk-screened outline that surrounds most LGA 1156 sockets.
Notice that all of today’s coolers extend beyond the outline that surrounds the socket. Base height can also be used to determine maximum memory height for DIMMs that fall under the cooler’s front fan.
Noctua’s NH-D14 gets an asterisk following its DIMM intrusion number because this particular cooler has a center fan that can be used with or without the front fan. Removing the front fan lessens DIMM encroachment by 25mm, though it also reduces the performance of the heat sink.
Putting a 92mm cooler up against the 120mm versions from your competitors takes guts, but that’s exactly what Arctic Cooling chose to do, even after being informed that our particular test would use a highly overclocked Core i7 processor. This is obviously a value play, as the company also produces a 120mm-based Freezer XTREME Rev.2 that costs almost twice as much. With a low Web price of around $25, we’re anxious to find out if this tiny unit can take the heat.

The Freezer 7 Pro Rev.2 ships with thermal paste that is pre-applied and protected by a clear plastic cover. Removing the paste reveals a super-flat copper base with a finely-sanded finish.

Supporting Intel’s desktop LGA processors (775, 1156, and 1366) and AMD’s clip-on socket frame (939, AM2, AM2+, and AM3), the Freezer 7 Pro Rev.2 is one of the few “performance” coolers that can replace a stock Intel cooler without removing the motherboard from a case.

Expansion plugs and wedges make bracket installation easy because low cooler weight and moderate spring pressure made a rear support plate unnecessary. Access to the front mounting screw is eased by unclipping the fan and extracting the wedges for bracket removal requires nothing more than a pair of long-nose pliers.

AMD fanatics will be a little more disappointed with their installation options, since the socket orientation of most AM2/AM3 motherboards will force them to mount the cooler with the fan blowing upwards from above the video card rather than in the proper cross-draft configuration.
One of the least-expensive 120mm tower coolers available, Cooler Master’s $30 Hyper 212 Plus still offers many of the features that make its competitors perform well.

Cooler Master adds even more value to its low price by supporting most current processor sockets, including LGA 1156, LGA 1366, LGA 775, Socket AM2, AM2+, and AM3. The company also adds a secondary fan bracket for creating an optional push-pull fan arrangement.

Direct-contact heat pipes respond quickly to changes in temperature, although manufacturers of competing designs might argue that they don’t actually remove more heat. A sanded finish provides excellent flatness at low cost, but relies more heavily on heat paste compared to smoother parts.

Four bolts act as spacers for the bracket screws, each with a threaded hole in its head for receiving those screws. The bolts are secured from underneath by nuts, with a socket support plate stiffening the board. These parts must be attached to the motherboard before it can be inserted inside most cases.

The sink and bracket can be installed or removed after the rest of the system is assembled, but the fan must be unclipped from the sink to reach the bracket’s front screws.
Care must be taken not to over-tighten the bracket screws, as doing so causes them to stick to the bolt. Loosening a bracket screw when it’s stuck to the bolt can cause the bolt itself to turn, freeing the nut that holds it from the under the motherboard. We’ve seen some of Cooler Master’s competitors use reverse (left-hand) thread hardware for under-side parts to prevent this problem, although that solution is a bit more confusing to builders.
Austrian firm Noctua has earned an impressive reputation in just a few years for its designs that offer excellent cooling-to-noise ratios. More recently, the firm translated its technical prowess into an enormous cooler that should, by way of sheer size, be able to outperform most competitors' devices. Roughly 50% bigger than the average “big air” competitor, the NH-D14’s $90 Web price is also around twice as expensive.

A great deal of installation flexibility adds some value to that high price, with support for single or dual fans and a full range of LGA 1156, LGA 1366, and LGA 775, plus AM2, AM2+, and AM3 processors. Noctua also adds two fan resistor wires for manual speed reduction.

An ultra-fine machined finish holds a thin film of thermal compound well, without being prone to the distortion that normally accompanies the polishing process. The NH-D14 appears to have the flattest mating surface of today’s competitors.

Noctua claims many innovations in fan design, but perhaps the most innovative feature of the NH-D14 is its multi-fit LGA support plate. Peeling the center portion of its rubber pad allows the plate to fit perfectly on LGA-1156 motherboards, with full mounting pressure against the motherboard’s integrated support plate relieving pressure from the circuit board.

Two curved brackets adapt LGA sockets from a four-screw to a two-screw mounting. These brackets, along with associated spacers, screws, and nuts, must be installed before the motherboard is placed inside most cases. Installing the sink inside or outside the case is as easy as unclipping the center fan to gain access to those two screws.
Surface area is one of the biggest factors in air-cooling efficiency and, at around $40, Scythe’s Mugen 2 Rev. B (spelled with or without the hyphen and abbreviated name) provides the greatest surface area per price of today’s competitors. Yet surface area is not the sole determining factor for performance, so we’ll rely on testing to determine how well this extra size is used.

Pressure relief grooves are Scythe’s innovative solution to the aerodynamic drag that accompanies long cooling fins. Without these grooves, a greater amount of air pressure would be lost out the sink’s sides.

The Mugen 2 Rev. B surprised us by supporting Socket 478 motherboards, in addition to the expected LGA models (1156, 1365, and 775) and AMD sockets (939, 940, AM2, AM2+, and AM3).

The Mugen 2 has one of the flattest polished bases we’ve seen, with distortion that normally occurs from the polishing process, which is only noticeable as a rounded edge. The copper base appears to be plated in nickel to prevent oxidization.

The Mugen 2 Rev. B’s greatest design weakness is that it usually must be installed outside the case, with screws that can only be accessed from beneath the motherboard. One of its strengths is that once installed, its fan can be slid up to allow greater DIMM clearance or down to further assist motherboard voltage-regulator cooling.
One of the oldest products in today’s comparison, Sunbeamtech’s highly-respected Core-Contact Freezer has recently been updated to support LGA 1156 processors. Priced at around $40 with an LGA 775 adapter and AMD clip, Sunbeamtech’s additional adapter brackets typically cost around $10.

The LGA 1156 adapter includes four mounting screws and a support plate. The long-present LGA 775 adapter still comes with the basic kit and AMD’s clip bracket is supported natively.

The Core-Contact Freezer gets its name from the four heat pipes that interface directly with the processor’s heat spreader, a popular design among several of today’s competitors. The design reduces both cooler weight and latent heat, although claims of better overall cooling are somewhat suspect. Like its competitors, Sunbeamtech sands the bottom of its pipes flat to minimize voids between its base and the processor, requiring a minimal amount of thermal compound to achieve excellent thermal transfer.

As an AMD-style clip-on cooler, the biggest hurdle for LGA motherboard compatibility is the clip itself. Minimal space between one of the adapter’s hooks and some voltage-regulator components forced us to tilt the cooler to install the top clip, before using the bottom clip in the conventional manner.

Because the Core-Contact Freezer uses an AMD-style clip, it can be installed in most recent AMD systems (939, AM2, AM2+, and AM3) without motherboard removal. Similarly, a push-pin style LGA 775 adapter bracket allows easy installation in those systems. LGA 1156 installation is less convenient but more secure, as the adapter’s support plate must be installed behind the motherboard to provide the threaded holes for its screws.
Packed in the same brown box as the original sample we’ve used in all our P55 motherboard roundups, Thermalright’s $50 MUX-120 has a few improvements compared to the OEM samples most reviewers received from Intel.

Chief among its updates is a screw-on bracket kit that’s also available separately from Thermalright. Other changes mostly focus on the manufacturing process, although the fan has also been replaced.

The MUX-120 has the best-looking socket support plate, with all the right clearance holes and threaded collars that easily slip into the motherboard’s mounting holes. Unfortunately, it doesn’t offer the added socket support we’d hoped for, as the center doesn’t actually touch the LGA 1156 back plate. The load that’s placed on the PCB (rather than on the back of the socket) is still relatively light, since this lightweight cooler requires only moderate spring pressure to seat firmly.

The MUX-120’s base is almost perfectly flat, with a fine machined finish that requires barely any paste to fill small voids. Ultra-thin plating prevents oxidation of the copper base without having a noticeable effect on thermal transfer (at least in theory).

Thermalright’s LGA 1156 “bolt-through” installation kit installs easily, with extra-long threaded collars on the base plate that prevent cross braces from touching any live circuits on the motherboard’s surface. Those parts must be installed prior to fitting the motherboard in a case, but the cooler and its bracket can be installed and removed from an assembled system. Side clips on the MUX-120 ease fan installation and removal, allowing access to the cooler bracket’s front screw.
A major player in both the retail and OEM cooler industry, the Frio might be Thermaltake’s most ambitious project to date. Two high-speed adjustable fans and five large heat pipes set the Frio apart from Thermaltake’s previous efforts.

Our pre-production unit arrived unboxed, but it did include all the hardware needed for Intel’s LGA 1156, 1366, and 775 processors, plus AMD’s Socket AM2, AM2+, and AM3 devices. Rubber washers prevent the LGA mounting tabs from contacting the motherboard’s top surface.

A chrome finish covers the pipes, while the base plating appears to be nickel. This plating is applied over an unpolished, finely sanded surface.

Installation is super-easy outside of a case, but removing the cooler with the motherboard installed requires a chassis that has an access hole in the motherboard tray beneath the CPU. If cooling performance matches its aggressive looks, this could be a great cooler for bench testing.
Unfortunately, the missing retail box is accompanied by a missing retail price. Thermaltake launched the Frio at CES, so we expect to see it reach our favorite sellers soon.
While our experience with the Tuniq brand is extremely limited, a quick look at the design elements of Tuniq's $60 Tower 120 Extreme back up its claims of design innovation.

To begin with, the Tower 120 Extreme is the first cooler in today’s comparison that uses fully-enclosed sides, something that’s critical in a pull fan arrangement, but still helpful with push fans. The Tower 120 Extreme is both, since its fan is located internally between two sink halves. By placing it in the center, Tuniq protects the LED fan from damage while creating a unique look as light escapes from between and under the sink’s fins.

A built-on bracket supports both AMD and Intel processors, including Socket 939, AM2, AM2+, and AM3 and LGA 775, 1156, and 1366. AMD adapter brackets and an Intel LGA support plate complete the installation kit.

Tuniq is one of several manufacturers to use direct-touch heat pipes to reduce latent heat and cooler weight. A finely sanded finish maintains excellent flatness for improved CPU contact, although grooves along each heat pipe’s edge slightly reduce the contact area.

LGA 1156 and 1366 installation begins by installing screws and nuts onto the support plate to create threaded studs that slip through the motherboard’s mounting holes. Spring-loaded nuts then secure the cooler against the CPU. The support plate must be added to the motherboard prior to fitting the motherboard inside cases, although the cooler itself can be installed and removed from inside any case that’s large enough to allow access to the cooler’s hold-down nuts.
Xigmatek coolers are popular for good reasons, which include quality appearance, good cooling capacity, and moderate price, but the company is taking its time updating the installation kit of several products to support Intel’s LGA 1156 interface. The firm had to add its Crossbow multi-platform LGA installation kit in order to qualify any of its super-sized coolers for today’s review.

Targeted at the enthusiast market, the Thor’s Hammer heat sink is intended to be used with the enthusiasts’ choice of favorite fans. Adding two of its Crystal-branded blue-LED clear fans to the package brings the total cost of this combination to $91, including the $65 sink and $8 Crossbow mounting kit. The Crossbow LGA 775, 1156, and 1366 bracket set is expected to replace the included LGA 775 and 1366 brackets in future packages. LGA 1156 users who want to save a little money will thus need to pay close attention to the product description listed by their favorite seller to determine when the package has been updated.


Direct-contact heat pipes highlight several elements of Thor’s Hammer production, including its black-nickel finish and relatively wide crevices between the pipes and base. Although the base and pipes are extremely flat, extra paste is required to fill the gaps for optimal contact area.

The Crossbow installation kit’s socket support plate attaches to the back of the motherboard via pre-applied self-adhesive film, while spring-loaded screws hold the cooler against the CPU via the support plate’s threaded holes. Because the cooler body prevents screwdriver access from above, Xigmatek includes a small wrench that can be used to tighten or loosen the screws from under the sink’s fins. Although removal and reinstallation are theoretically possible from inside some cases, this extremely tedious task is significantly eased by installing the cooler with both fans removed outside of any case.
Zalman usually impresses us with the quality of its products, but quality doesn’t always come cheap. A $60 Web price makes this one of the more expensive single-fan coolers in today’s test.

Great news for fans of motherboards not based on an LGA 1156 interface is that the CNPS10X Quiet also supports LGA 1366 and LGA 775 platforms, in addition to AMD’s Socket 939, AM2, AM2+, and AM3 standard brackets. However, we are a little concerned about how such a large cooler is installed in Core i5 and Core i7 motherboards without a support plate, using little more than four nuts from underneath to support its top-side mounting bracket.

Zalman’s Fan Mate 2 is yet another expense that could help balance the value in the CNPS10X Quiet. However, we prefer dynamic fan speed through BIOS and the included three-pin fan does not support the pulse-width modulation method that so many motherboards enable.

A gold-plated, polished base is one of Zalman’s quality traditions. Yet, like most polished coolers, this one isn’t completely flat. Thermal paste fills any small voids that result from installing a heat sink on a processor’s heat spreader. The gold is thick enough to prevent oxidization without being so thick as to hinder heat transfer to the copper plate beneath.
Installing the CNPS10X Quiet begins by adding its plastic bracket to the motherboard, a process as easy (or difficult) as putting screws through the top side and adding tiny plastic washers and nuts to the bottom. This must be done before the motherboard is installed in a case.

The cooler-retention bracket clamps the heat sink base firmly over the CPU via spring-loaded screws. The fan must be removed to gain access to the front screws, but wire clips make its removal and replacement a simple process.
Orientation of the AMD-compatible clip forces an updraft rather than cross-draft installation on most motherboards. This should make the CNPS10X Quiet an Intel-only cooler design in the minds of most enthusiasts.
| Test System Configuration | |
|---|---|
| CPU | Intel Core i7-870 (2.93 GHz, 8MB Cache), O/C to 4 GHz (20 x 200 MHz), 1.388V |
| Motherboard | EVGA P55 SLI E655, P55 Express PCH, BIOS A39 (10/23/2009) |
| RAM | Crucial CT2KIT25664BA1339 (4GB), DDR3-1333 at DDR3-1600 CAS 8-8-8-24 |
| Graphics | Diamond Radeon HD 5870 1GB, 850 MHz GPU, GDDR5-4800 |
| Hard Drive | Western Digital Velociraptor WD3000HLFS, 300GB, 10,000 RPM, SATA 3 Gb/s, 16MB cache |
| Sound | Integrated HD Audio |
| Network | Integrated Gigabit Networking |
| Power | Corsair CMPSU-850HX 850W Modular, ATX12V v2.2, EPS12V, 80-Plus Gold |
| Software | |
| OS | Microsoft Windows 7 Ultimate x64 |
| Graphics | ATI Catalyst 9.11 |
| Chipset | Intel INF 9.1.1.1015 |

Still warm from our most recent PCI Express Scaling comparison, EVGA’s P55 SLI was retained for the “just right” overclock settings that were already programmed into it. We wanted to approach (but never reach) the processor’s thermal limit and these settings worked perfectly for nine of the 10 coolers.
Several coolers hung over the memory slots of our motherboard, preventing the use of memory with tall heat spreaders. We skipped the heat spreader issue entirely by using Crucial DDR3-1333 modules, yet were still able to use DDR3-1600 settings.

| Benchmark Configuration | |
|---|---|
| Prime95 v25.8 | 64-bit executable, small FFTs, 8 threads |
| RealTemp 3.00 | Highest core reading at full CPU load (60 minutes) Highest core reading at 30 minutes idle |
| Acu-Rite thermal probe | VRM temperature Ambient temperature at 6" from the motherboard's front edge |
Priced at around $150, Galaxy’s CM-140 has gotten a great deal of attention on the Web as one of the broadest-range, most accurate SPL meters available for under $400. We love a great deal!

Taking a cue from the audio world, we wanted to gauge all of today’s performance coolers at a distance of one meter. The problem for us is that the bottom of our SPL scale is 30db, and the meter is only accuracy rated for decibel levels of 32db or higher. In order to get a “higher” reading from quieter parts, we measured each cooler at 0.25m and then used one of several SPL conversion applications to convert our readings to one meter.
However, the method isn’t perfect--testing several items of known SPL values revealed a consistent 1db (lower) difference that might be attributable to improper meter calibration. To compensate, we added 1db to all of our measurements.
We tested each cooler with it stock fan(s), and then retested with our own choice of a 2,500 RPM fan to find out how well each heat sink worked at similar noise levels and airflow. The chart below is organized by stock fan performance.

Noctua and Scythe had the largest sinks, so it’s no big surprise that these coolers offered the best performance with the dual-fan NH-14 in the lead. Yet there is a surprise near the middle of this chart: Thermalright’s thin MUX-120 takes second place when our custom fan is used. Middling performance for the stock configuration can be attributed to a low-speed stock fan.
Note that Arctic Cooling’s Freezer 7 Pro Rev.2 reaches an astounding 82 degrees Celsius over-ambient temperature with our highly overclocked processor. This is not a typo! We were forced to drop the lab temperature to a chilly 11 degrees Celsius to complete its evaluation.
Also worth mentioning is that the top four contenders in today’s comparison did not use direct-contact heat pipes, but instead relied upon copper heat spreaders to interface the integrated heat spreader of our CPU. If we instead look at the results obtained using our own fan, Thermaltake’s Frio drops out while Thermalright’s MUX-120 drops in and we’re still left with the top four performers lacking this so-called “feature.”

A fan that hangs below the cooler and an open center allowed Thermalright’s MUX-120 to provide excellent airflow over our system’s voltage regulator. Two peculiarities in this test are that the Thermaltake Frio cools the VRM poorly with our single fan, while Arctic Cooling’s Freezer 7 Pro Rev.2 excels with the replacement fan. Arctic Cooling’s dramatically improved performance is explained by how the edge of the replacement fan rested on top of the motherboard, producing interesting results from an otherwise impractical configuration.
Fan speed is the biggest factor in both noise levels and airflow, two things that manufacturers must carefully consider before launching any new cooling product. One might thus expect the noisiest cooler to be the most powerful, although sink design is often more important.

Thermalright’s moderate cooling performance is achieved with a surprisingly low-speed fan, while Thermaltake’s Frio spins over twice as fast at maximum speed. Potentiometers on the Frio’s fans allow these to be slowed, but it would have been impossible test the infinite number of available settings.

Running at slightly less than its rated speed, our Thermalright MUX-120 sample also produced slightly less noise than its rated maximum. Scythe’s second-place quietness is impressive in light of its second-place cooling performance.
The easiest way to figure out which cooler provides the best cooling-to-noise ratio is to convert each observation to a percentage, relative to other coolers in the test. We divided the average temperature produced by all coolers by the actual temperature produced by each cooler to create a temperature-percent scale. A separate noise-percent scale divides each cooler’s SPL by the average noise of all coolers. Dividing each cooler’s temperature ranking by its noise ranking allows a number to be assigned to its acoustic efficiency, aka "cooling-to-noise ratio.”

Thermalright’s supremely quiet fan and mid-pack cooling performance team up to give the MUX-120 a first place cooling-to-noise finish. Scythe’s mid-speed fan and huge sink allow its Mugen-2 Rev. B to retain second place.
Applying the same calculation method used above to temperature and price allows value to be assessed numerically.

The above chart comes with a big caveat: while Cooler Master’s Hyper 212 Plus provided enough cooling for our 4 GHz CPU, the Freezer 7 Pro Rev.2 did not. Thus, while Cooler Master’s low $30 price makes it a great deal for ambitious overclockers, the Freezer 7 Pro Rev.2 is better suited for less enthusiastic tweakers.
Four coolers that stood out today for superiority in various areas are Noctua’s top-cooling NH-D14, Thermalright’s nearly-silent MUX-120, Cooler Master’s superb-value Hyper 212 Plus, and Scythe’s jack-of-all-trades Mugen-2 Rev. B. Yet the one we’d use and the one we’d recommend might be completely different parts.
Even though the cooler cost $10 more, it’s impossible to ignore the six degrees Celsius cooling advantage Scythe’s Mugen-2 Rev. B provided over Cooler Master’s low-cost Hyper 212 Plus. Our biggest reservation in recommending it universally to budget-oriented overclocking enthusiasts is that it’s the second-biggest sink in the comparison. Putting the fan on the front causes it to hang over the memory slots of most motherboards, discouraging builders who prefer high-profile memory cooling..
At over twice the Mugen-2 Rev. B’s price, the Noctua NH-D14 exacerbates the fitment issue by extending even farther over DIMMs. An impressive 42mm of clearance beneath its bottom fins and adjustable fan height allow at least modest clearance for memory heat spreaders, although there still isn’t enough room for high-performance memory cooling. Yet, while the NH-D14’s sheer size will put off many buyers, class-leading performance and the ability to install and remove the sink from inside a traditional case is sure to put it on the wish lists of many extreme-air enthusiasts.
While we don’t want to dismiss the excellent value of Cooler Master’s $30 Hyper 212 Plus, we were even more impressed to see Thermalright’s thinner sink and ultra-quiet fan provide even greater cooling performance. Unfortunately, Thermalright’s better performance comes at a significantly higher price of $50, hurting its standing in our value charts.
The combination of pros and cons leave us with several recommendations, depending on intended use. While Noctua’s customers have probably already committed themselves to purchasing the best-performing CPU air cooler, we’d recommend the cheaper Mugen-2 Rev. B as a better value for nearly any configuration that has the necessary mounting space. Thermalright’s MUX-120, on the other hand, is the best performing solution for builds that have limited mounting space, while Cooler Master’s far cheaper Hyper 212 Plus is worth considering by anyone who requires a similar footprint but can’t live with Thermalright’s higher price.
With our recommendations out of the way, it’s worth noting that while several coolers included manual fan speed controllers, only three supported pulse-width modulation (PWM) fan speed control. Of those, Scythe’s Mugen-2 Rev. B was the only one to make its way into our recommendations based on performance alone. We see many of our readers express frustration over their motherboards' “inability” to control fan speed automatically, but many of those boards rely on PWM control exclusively. While some motherboards also provide for fan-speed control via automatic voltage changes, PWM fans work with either type of speed control. Automatic speed control is a far more valuable feature to us than any included potentiometer, because we prefer our systems to be nearly silent under low load. Thus, while we’ve ignored the feature in our performance analysis, this editor has taken the initiative to replace the fan of his own MUX-120 test cooler with a PWM-based unit.
