Enermax ETS-T40: Direct-Touch Heatpipe Cooler

The Enermax ETS-T40 tower CPU heatsink/fan is equipped with an impressive looking mounting system, a surprisingly smooth sounding fan, and an affordable price. Unfortunately the one thing missing is great performance.

July 23, 2012 by Lawrence Lee

Product	Enermax ETS-T40-TB CPU Cooler
Manufacturer	Enermax
Street Price	US$35

Enermax is a veritable legend in the PC power supply market but like many other manufacturers, they’ve expanded their range to cases and cooling products. Diversification is the general strategy for survival in the face of changing tech market patterns. Our first Enermax CPU heatsink sample is yet another ubiquitous tower, a budget model equipped with direct-touch heatpipes and their distinct “Twister” 120 mm fan.

The ETS-T40 box and contents.

Unlike some companies, Enermax isn’t particularly fussy with their packaging. The ETS-T40 ships in a simple white box with blue accents, just large enough for the heatsink and accessories. The ETS-T40 is a simple four heatpipe 160 mm tall cooler in the same vein as the Cooler Master Hyper 212 Plus, the current undisputed low-cost heatsink; it’s not a bad design to emulate. We’ve seen direct-touch heatpipe models come and go but most of them have been cursed with a poor mounting system resulting in less than adequate pressure between the base and CPU heatspreader.

Accessories.

One look at the ETS-T40’s mounting gear and we’re optimistic. A simple metal frame is assembled around the socket and a thick bar goes over the base exerting a downward force, a system similar to that employed by Noctua, Prolimatech, and Thermalright on their high performance coolers. A second set of fan clips is also included for those who prefer to utilize a dual fan configuration.

Enermax ETS-T40: Key Features (from the product web page)
Feature & Brief	Our Comment
World leading thermal resistance performance of 0.09°C/W. – Patented VGF (Vortex generator flow) technology to greatly increase air convection. – Patented SEF (Stack Effect) design to enhance heat transfer. – Unique air path creating high VEF (Vacuum Effect) to optimize the airflow. – Patented HDT (Heat Pipe Direct Touch) Technology to ensure rapid thermal conduction and eliminate CPU hotspot.	Every manufacturer claims their design is optimized for maximum performance.
Side flow type with four Ø6mm high performance heat pipes.	A standard design.
Unique T.B.Silence PWM fan to adjust the power efficiently and keep the silence.	Unique yet alike to every other PWM fan.
Dual fan installed option and solid springs attached.	Typically only useful on thick heatsinks but having the option is a bonus.
Anti-vibration rubbers prevent fan vibration and absorb noise.	Dampens vibrations and also creates some separation between the heatsink and fan.
Universal bracket for Intel® 775/1155/1156/1366/2011 and AMD® AM2/AM2+/AM3/AM3+/FM1.	Good.
High thermal conductivity grease to ensure the best thermal conduction between CPU and the heat sink.	We’ll take their word for it.

 

Enermax ETS-T40: Specifications (from the product web page)
Model	ETS-T40-TB
Compatible Socket	Intel® LGA 775/1155/1156/1366/2011, AMD® AM2/AM2+/AM3/AM3+/FM
Overall Dimension	139(L) x 93(W) x 160(H)mm
Heat Sink Dimension	139(L) x 70(W) x 160(H)mm
Weight	610g
Heat Pipe	4 x Ø6mm
Material	Copper heat pipes, aluminum fins
Thermal Resistance	0.09°C/W
Thermal Grease	Dow Corning® TC-5121
Fan Dimension	120 x 120 x 25 mm
Fan Speed	800 ~ 1800 RPM
Air Flow	37.57 ~ 86.70CFM 63.83 ~ 147.30m3/h
Static Pressure	0.72 ~ 2.41mmH2O
Rated Voltage	12V
Bearing Type	Twister Bearing
MTBF	100,000 hours
Noise	10 ~ 21dBA
Connector	4 pin PWM connector

PHYSICAL DETAILS

The Enermax ETS-T40 is composed four 6 mm thick copper direct-touch heatpipes friction-fit to just 52 aluminum fins. The heatsink is 160 mm tall, a common height for tower coolers. According to our digital scale, it weighs approximately 620 grams bare and about 840 grams total with the fan secured.

The most interesting feature of the heatsink is the fan design of the included Twister fan, a 120 mm model with bat-like blades and holes cut into the sides spelling out the Enermax name. As the ETS-T40 has an inset to accommodate it, 140 mm fans are not compatible without modification.

The fan-side surface of the heatsink is also unusual, with four distinct ridges and a large trough in the middle. The separation at the center between the heatsink and fan is a full centimeter. Triangular columns have been cut from the fins similar to the Thermalright HR01/02 Macho with their “through holes” but they appear more decorative than functional in this case.

Right out of the box, one of the fin corners was bent. This tends to be a problem for unanodized/plated fins. The fins are also closed on the sides in the center which creates a possible a ventilation issue.

The fan has a black frame and grey/translucent blades, though our particular ETS-T40-TB variant lacks LED fans (look for the suffix –TA and –VD if you like lighting). Notice the rubber dampening pads adhered to the edges.

On average, the fins are 0.40 mm thick and spaced 1.79 mm apart. It’s a fairly tight grouping compared to most modern tower heatsinks. We don’t expect it to have great low airflow performance.,

The heatpipes are almost perfectly flat and the surface has a nice, shiny finish. Some light circular machine marks are visible.

INSTALLATION

The most critical aspect of installation is that the heatsink be securely
mounted. A firm mating results in good contact between the heatsink’s base and
the CPU heatspreader and more efficient heat conduction. Ideally it should
also be a simple procedure with the user having to handle as few pieces of
hardware as possible.

Installation begins by securing the backplate using double-sided screws. Note there are no nuts, the threads are directly on the backplate.

Raised mounting clips are assembled on the top side of the board.

Small nuts are used to batten down the clips, the heatsink is lowered onto the CPU, and a substantial metal bar is placed over the base. One large nut on each side keeps the heatsink in place. A small wrench is provided to ensure a tight fit.

Fully mounted on our LGA1366 testing platform.

Clearance beneath the heatsink is approximately 44 mm, though this shouldn’t be an issue. Most motherboard VRM heatsinks aren’t that tall and ETS-T40 is thin enough that the fan may not overhang any memory slots.

TESTING

Before thermal testing, we took some basic physical measurements.

Approximate Physical Measurements
Weight	620 g 840 g w/ fan and clips
Height	160 mm
Fin count	52
Fin thickness	0.40 mm
Fin spacing	1.79 mm
Vertical Clearance*	44 mm
* measured from the motherboard PCB to the bottom fin of the heatsink

 

Large Heatsink Comparison: Average Fin Thickness & Spacing
Heatsink	Fin Thickness	Fin Spacing
Thermalright HR-01 Plus	0.45 mm	3.15 mm
Thermalright HR-02 Macho	0.34 mm	3.12 mm
Scythe Ninja 3	0.39 mm	2.64 mm
Noctua NH-U12P	0.44 mm	2.63 mm
Noctua NH-C12P	0.47 mm	2.54 mm
Noctua NH-D14	0.43 mm	2.33 mm
Thermalright Archon SB-E	0.49 mm	2.33 mm
be quiet! Dark Rock 2	0.38 mm	2.22 mm
Prolimatech Armageddon	0.51 mm	2.08 mm
Prolimatech Megahalems	0.50 mm	2.00 mm
Zalman CNPS10X Quiet	0.40 mm	2.00 mm
Scythe Kabuto & Zipang 2	0.34 mm	1.94 mm
NZXT Havik 140	0.41 mm	1.91 mm
Scythe Mugen-2	0.31 mm	1.89 mm
Swiftech Polaris 120	0.43 mm	1.85 mm
Thermalright Venomous X	0.53 mm	1.84 mm
Noctua NH-C14	0.38 mm	1.79 mm
Enermax ETS-T40	0.40 mm	1.79 mm
Scythe Yasya	0.32 mm	1.78 mm
Cogage TRUE Spirit 1366	0.40 mm	1.70 mm
Arctic Cooling Freezer Xtreme Rev.2	0.30 mm	1.70 mm
Scythe Grand Kama Cross	0.38 mm	1.66 mm
Reeven Kelveros	0.47 mm	1.61 mm
Zalman CNPS9900 MAX	0.16 mm	1.59 mm
Thermalright Silver Arrow	0.32 mm	1.57 mm
Cooler Master Hyper 212 Plus	0.43 mm	1.54 mm
Thermalright Ultra-120 eXtreme Rev.C	0.56 mm	1.52 mm
Zalman CNPS10X Extreme	0.42 mm	1.50 mm

Testing on larger heatsinks are done on our
LGA1366 heatsink testing platform, while smaller coolers tackle our LGA1155 heatsink testing platform. A summary of the test system
and procedure follows.

Key Components in LGA1366 Heatsink Test Platform:

• Intel Core i7-965 Extreme
  Nehalem core, LGA1366, 3.2GHz, 45nm, 130W TDP.
• Asus
  P6X58D Premium ATX motherboard. X58 chipset.
• Asus
  EAH3450 Silent graphics card.
• Intel
  X25-M 80GB 2.5″ solid-state drive. Chosen for silence.
• 3GB QiMonda
  DDR3 memory. 3 x 1GB DDR3-1066 in triple channel.
• Seasonic X-650 SS-650KM
  650W ATX power supply. This PSU is semi-passively cooled. At the power levels
  of our test platform, its fan does not spin.
• Arctic Silver
  Lumière: Special fast-curing thermal interface material, designed
  specifically for test labs.
• Noctua 140 mm fan (used when possible with heatsinks that fit 140x25mm
  fans)
• Nexus 120 mm fan (used when possible with heatsinks that fit 120x25mm
  fans)
• Nexus 92 mm fan (used when possible with heatsinks that fit 92x25mm
  fans)

The systems are silent under the test conditions, except for the CPU cooling
fan(s).

Normally, our reference fans are used whenever possible, the measured details
of which are shown below.

Reference Noctua 140mm fan Anechoic chamber measurements
Voltage	SPL@1m	Speed
12V	28~29 dBA	1250 RPM
9V	21 dBA	990 RPM
7V	15~16 dBA	770 RPM
6V	13 dBA	660 RPM

 

Reference Nexus 120mm fan Anechoic chamber measurements
Voltage	SPL@1m	Speed
12V	16 dBA	1100 RPM
9V	13 dBA	890 RPM
7V	12 dBA	720 RPM

 

Reference Nexus 92 mm fan Anechoic chamber measurements
Voltage	SPL@1m	Speed
12V	16 dBA	1470 RPM
9V	12 dBA	1150 RPM

Measurement and Analysis Tools

• Extech 380803 AC power analyzer / data logger for measuring AC system
  power.
• Custom-built, four-channel variable DC power supply, used to regulate
  the fan speed during the test.
• PC-based spectrum analyzer:
  SpectraPlus with ACO Pacific mic and M-Audio digital
  audio interfaces.
• Anechoic chamber
  with ambient level of 11 dBA or lower
• Various other tools for testing fans, as documented in our
  standard fan testing methodology.
• SpeedFan,
  used to monitor the on-chip thermal sensors. The sensors are not calibrated,
  so results are not universally applicable. The hottest core reading is used.
• Prime95,
  used to stress the LGA1366 CPU heavily, generating more heat than most real applications.
  8 instances are used to ensure that all 4 cores (with Hyper-threading) are
  stressed.
• CPU-Z,used to monitor the CPU speed to determine when overheating occurs.
• Thermometers to measure the air temperature around the test platform
  and near the intake of the heatsink fan.

Noise measurements are made with the fans powered from the lab’s variable DC
power supply while the rest of the system was off to ensure that system noise
did not skew the measurements.

Load testing was accomplished using Prime95 to stress the processor, and the
graph function in SpeedFan was used to ensure that the load temperature is stable
for at least ten minutes. The temperature recorded is the highest single core
reading. The stock fans were tested at various voltages to represent a good
cross-section of airflow and noise performance.

The ambient conditions during testing were 10~11 dBA and 21~23°C.

Stock Fan Measurements

Specifications: Enermax ETS-T40 Stock Fan
Manufacturer	Enermax	Power Rating	5.4 W
Model Number	PD122512MP-N	Airflow Rating	37.57 ~ 86.70 CFM
Bearing Type	Twister (sleeve)	Speed Rating	800 ~ 1800 RPM
Corners	Open	Noise Rating	10 ~ 21dBA
Frame Size	120 x 120 x 25 mm	Header Type	4-pin
Fan Blade Diameter	110 mm	Starting Voltage	< 5.0 V
Hub Size	39 mm	Weight	120 g
Data in green cells provided by the manufacturer or observed; data in the blue cells were measured.

 

Stock Fan Measurements
Voltage	Speed	SPL@1m
12V	1930 RPM	35~36 dBA
9V	1520 RPM	28 dBA
7V	1060 RPM	20 dBA
6V	820 RPM	14 dBA
5V	580 RPM	11~12 dBA
Measuring mic positioned 1m at diagonal angle from the center of the heatsink. Ambient noise level: 10~11 dBA.

The Twister fan’s acoustics are excellent through most of its range. At 9V and above, it is very loud and fairly buzzy, a typical characteristic of sleeve bearing models. At lower speeds, it has a very smooth, pleasant sound. It is a high speed model though (our sample was 130 RPM faster than its rated speed) so it is quite loud until about the 7V / 1060 RPM level. At 5V / 580 RPM it’s effectively inaudible.

At 7V, the stock fan emits a noise level of 20 dBA@1m.

The fan has no audible tonality, as indicated by the lack of peaks in our acoustic analysis. The noise generated is distributed fairly evenly frequency-wise, giving it a smooth broadband profile.

TEST RESULTS

Enermax ETS-T40
Fan Voltage	Fan Speed	SPL@1m	°C Rise
Stock Fan
12V	1930 RPM	35~36 dBA	42
9V	1520 RPM	28 dBA	43
7V	1060 RPM	20 dBA	49
6V	820 RPM	14 dBA	55
5V	580 RPM	11~12 dBA	64
Reference Nexus 120mm Fan
12V	1080 RPM	16~17 dBA	44
9V	880 RPM	13 dBA	46
7V	720 RPM	12 dBA	50
Reference Nexus 120mm Fan x 2
12V	1080 RPM	20 dBA	41
9V	880 RPM	15 dBA	43
7V	720 RPM	13 dBA	47
°C Rise: Temperature rise above ambient (20°C) at load.

The ETS-T40 performed well only with its stock fan at very high speeds. A large drop in performance occurred when the fan voltage was lowered below 7V. There was a 6°C increase going from 7V to 6V, and it took an additional 9°C hit at 5V. The ETS-T40 has the dishonor of being one of only a handful of heatsinks that have generated a thermal rise above ambient greater than 60°C on our testing platform. With these results alone, one might conclude that it’s a terrible cooler — but that’s only half-true.

When the stock fan was swapped with our trusty reference Nexus 120 mm fan, its performance picked up considerably. At 12V it emitted 16~17 dBA@1m, subjectively little more than half the noise of the stock fan’s 20 dBA@1m at 7V, yet the Nexus produced a CPU temperature 5°C lower. At 9V, it was 1 dB quieter than the stock fan at 6V but the Nexus had a massive 9°C advantage. Adding a second Nexus fan improved performance by 3°C.

Thermal compound footprint: ETS-T40 above, Hyper 212 Plus below.

After testing, we examined the thermal compound footprint and discovered a telltale sign of poor contact between the base and CPU. The ETS-T40 had noticeable veins of TIM spread out fairly evenly on its heatpipes. Contrast this to the Cooler Master Hyper 212 Plus (the best direct-touch heatpipe cooler we’ve ever tested), which had only trace amounts, and much of the important copper pipe sections were virtually clear. High mounting pressure pushes most of the excess compound to the sides leaving only a faint impression behind. (Editor’s Note: It’s also possible that the aluminum dividers between the flattened heatpipes in the Enermax heatsink protrude just a little too far so that pressure between the heatpipes and the CPU is limited.)

Heatsink Comparison Tables

CPU Coolers (ref. 120mm fan): °C Rise Comparison
Heatsink	Fan voltage / SPL @1m*
	12V	9V	7V
	15~16 dBA	12~13 dBA	11~12 dBA
Thermalright Ultra-120 eXtreme Rev.C	38	40	43
Thermalright Venomous X	38	41	43
Prolimatech Megahalems	38	41	44
Noctua NH-U12P	39	42	44
Scythe Mugen-2	39	42	45
Cogage TRUE Spirit 1366	40	42	45
Prolimatech Armageddon	40	42	46
Zalman CNPS10X Quiet	40	43	46
Noctua NH-C14	39	42	48
Scythe Yasya	41	43	47
Thermalright Ultra-120 eXtreme	40	43	48
Cooler Master Hyper 212 Plus	41	44	48
Thermalright Archon SB-E	42	43	49
Thermalright Ultra-120	42	45	49
Titan Fenrir	43	46	50
Scythe Ninja 3	44	47	49
Enermax ETS-T40	44	46	50
Noctua NH-C12P	43	47	51
Zalman CNPS10X Extreme	43	47	53
Swiftech Polaris 120	46	49	54
Zalman CNPS10X Flex	45	50	54
be quiet! Dark Rock 2	48	50	52
Cooler Master V8	46	50	54
Reeven Kelveros	47	51	55
Scythe Grand Kama Cross	45	52	57
Antec Kühler H20 620 (pump at 7V, almost inaudible)	52	52	53
Arctic Cooling Freezer Xtreme Rev.2	49	52	58
Scythe Kabuto	51	53	60
*Note: there are minor differences in measured SPL due to the variety of fan orientations and mounting methods offered by the compared coolers.

The ETS-T40’s middling performance with our reference fan puts it in the company of such heatsinks like the Scythe Ninja 3 and the Titan Fenrir; the latter is another direct-touch heatpipe model with a flawed mounting system that could use increased pressure.

MP3 SOUND RECORDINGS

These recordings were made with a high
resolution, lab quality, digital recording system inside SPCR’s
own 11 dBA ambient anechoic chamber, then converted to LAME 128kbps
encoded MP3s. We’ve listened long and hard to ensure there is no audible degradation
from the original WAV files to these MP3s. They represent a quick snapshot of
what we heard during the review.

These recordings are intended to give you an idea of how the product sounds
in actual use — one meter is a reasonable typical distance between a computer
or computer component and your ear. The recording contains stretches of ambient
noise that you can use to judge the relative loudness of the subject. Be aware
that very quiet subjects may not be audible — if we couldn’t hear it from
one meter, chances are we couldn’t record it either!

The recording starts with 5~10 second segments of room ambiance, then the fan
at various levels. For the most realistic results, set the volume so that
the starting ambient level is just barely audible, then don’t change the volume
setting again.

• Enermax ETS-T40 with stock fan at 1m
  — 6V (14 dBA@1m)
  — 7V (20 dBA@1m)
  — 9V (28 dBA@1m)
  — 12V (35~36 dBA@1m)

FINAL THOUGHTS

Ouyr first glimpse of the Enermax ETS-T40’s solid mounting system made us think that this could be the direct-touch heatpipe cooler that finally takes down the venerable Cooler Master Hyper 212 Plus, the king of budget heatsinks. But like the Reeven Kelveros, Swiftech Polaris 120, and Titan Fenrir before it, the ETS-T40’s mounting hardware doesn’t provide good enough contact between its base and the CPU. The end result is middling performance, and it’s only capable of that at high stock fan speed or more quietly when armed with a quality fan. The included Enermax Twister fan is a smooth sounding model that surprisingly delivers poor cooling proficiency at less than top speed with the ETS-T40. At comparable noise levels, our reference fan tromped it.

The ETS-T40 is yet another in a long line of flawed direct-touch heatpipe coolers with more bark than bite. High cost would make the ETS-T40 a complete blunder, but thankfully it has a very palatable street price of only US$35. But if you’re into quiet cooling, we don’t believe it’s worth even that much, not if one has to replace the fan to achieve acceptable cooling performance. It could work cool and quiet enough if your CPU runs cooler than our hot i7-1366. The aforementioned Cooler Master Hyper 212 Plus can be found for a mere US$25 or less at some e-retailers, however, and unless this model has changed significantly from the sample we tested two years ago, it is tough to match.

Our thanks to Enermax for the ETS-T40 CPU cooler sample.

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SPCR Articles of Related Interest:

be quiet! Dark Rock 2 Tower Heatsink
Thermalright HR-02 Macho Quiet/Fanless Cooler
Cooler Master GeminII M4 Low Profile Heatsink
Reeven Kelveros & Arcziel CPU Coolers
Thermalright Archon SB-E 15cm Fan CPU Cooler
Antec Kühler H20 620 & 920 CPU Water Cooling Units

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