Gelid Silent Spirit & Scythe Samurai ZZ CPU Coolers

Table of Contents

The Gelid Silent Spirit and Scythe Samurai ZZ are a pair of modestly sized top-down CPU coolers with 92 mm fans. While neither will win any performance awards, their size is an asset in cases too small for large heatsinks with 120/140 mm fans.

May 31, 2010 by Lawrence Lee

Product
Gelid Silent Spirit
CPU Cooler
Scythe Samurai ZZ
SCSMZ-2000
CPU
Cooler
Manufacturer
Gelid
Solutions
Scythe
Co., Ltd.
Street Price
US$30 US$30~$35

The Gelid Silent Spirit and Scythe Samurai ZZ are a pair of modestly sized
top-down CPU coolers with 92 mm fans. Such heatsinks are an appropriate choice
for the more common middle of the road processors found in most desktop PCs.
They are typically far superior than stock cooling solutions, but do not perform
nearly as well as large tower coolers. However, their size is an asset, particularly
in cases that are not wide enough to accommodate the plethora of big heatsinks
with 120/140 mm fans.

 


The Gelid Silent Spirit.

Gelid Silent Spirit

Though Gelid is a relatively new name in the business, it was founded by former
employees of Arctic Cooling, giving it instant credibility. Given the company’s
provenance, it’s no surprise to see the Silent Spirit’s fan has the same style
construction as some found on Arctic Cooling Alpine series of heatsinks. As
It lacks a tradition box casing, its impeller lays naked, visible from all sides.
The four struts bend at the edges forming feet that stand on a ring which is
attached to a clip-on frame using soft fan isolators. Great lengths have been
taken to prevent the fan from directly touching the heatsink and to dampen vibration.
Perhaps most interesting of all, the bulk of the heatsink does not lay flat
— it is uplifted a bit to one side so the fan blows slightly off to the side.


Mounting hardware.

The Silent Spirit comes with nothing inside the box aside from the heatsink,
a pair of plastic place-holders, and a set of AMD mounting clips. LGA775 clips
are pre-installed, and a square of thermal compound is pre-applied to the base.
LGA1366 clips are available but must be purchased separately.

Gelid Silent Spirit: Key Features
(from the product
web page
)
Feature & Brief Our Comment
Quad Sintered Heatpipes Nothing special.
Unique Fin Architecture Of course.
Special Heatsink Angle Design The heatsink’s ’tilt’ is designed to
exhaust air a bit more efficiently than blowing it straight down.
Optimized Air Flow Concept We’re still waiting for a heatsink manufacturer
to claim their product isn’t optimized.
Intelligent PWM Fan Control Curve They claim typical PWM fans speed up
linearly with CPU temperature while their fan has a more exponential curve.
Anti-Vibration Fan Mounts Soft-mounted Arctic Cooling style fan.

 

Gelid Silent Spirit: Specifications
(from the product
web page
)
*INCLUDED Pre-applied high performance thermal compound
Air Flow (CFM) 45.8 max
Bearing Hydro Dynamic Bearing
Cable Length (mm) 250
Cooling Performance (C/W) 0.17
Current (A) 0.23
Dimensions of Cooler (mm) 108 (l) x 100.5 (w) x 125 (h)
Dimensions of Fan (mm) 100.5 (l) x 100.5 (w) x 45 (h)
Dimensions of Heatsink (mm) 108 (l) x 97 (w) x 88.5 (h)
Fan Speed (RPM) 900 – 2400
Life time MTTF at 40C (h) 50’000
Noise Level (dBA) 10 – 25.8
Voltage (V) 12
Warranty (years) 5
Weight (g) 370

Scythe Samurai ZZ


The Scythe Samurai ZZ.

The Scythe Samurai ZZ takes a more straight forward approach. It’s a 3-heatpipe
cooler with a straight up-and-down design featuring a 92 mm Slip Stream fan.
The fan is mounted in a polar opposite method to the Silent Spirit, with a pair
of wire clips that clamp on very tightly — they’re actually difficult to
take off without pliers. If the two fans are similar noise-wise in free-air,
the Scythe would likely be louder given how it’s mounted. The Samurai ZZ has
an inherent performance advantage though since the fan housing helps generate
pressure by directing airflow downward and the fan is closer to the CPU and
motherboard PCB since the heatsink isn’t angled upward.


Included accessories.

The Samurai ZZ also boasts better compatibility. Its set of three mounting
clips allows it to be installed on all current AMD and Intel desktop platforms
and even socket 478.

Scythe Samurai ZZ: Key Features
(from the product
web page
)
Feature & Brief Our Comment
F.P.S. (Fast-Phase Structure)
Larger heatsink base and direct airflow towards lower heatsink block structure
to provide a high cooling efficiency with compact heatsink dimensions.
This refers to the smaller heatsink above
the base.
Top Mount Fan
By pointing the airflow of the fan towards the motherboard, Chip sets and
MOS-FETs on VR modules can be cooled simultaneously.
A simple downblowing cooler.
V.T.M.S. (Versatile Tool-free Multi platform
System)

Improved version of Versatile Tool-free Multi platform System allows multi
platform installation without any tools on the latest Intel and AMD sockets.
Looks more or less the same as the same
system used on the original Samurai Z 4 years ago.

 

Scythe Samurai ZZ: Specifications
(from the product
web page
)
Model Name SCSMZ-2000
Manufacturer Scythe Co., Ltd. Japan
Attachment VTMS Mounting Clips
Thermal Grease
Compatibility Intel® LGA1366, LGA1156, LGA775, S478
AMD Socket AM3, AM2+, AM2, 940, 939, 754
Heatsink
Dimensions 94 x 122 x 94 mm 3.7 x 4.8 x 3.7 in
Weight 472 g
16.6 oz.
Material: x3 Heat Pipes
Aluminum and Copper
Material of Base Plate Nickel-plated copper
Fan
Dimensions: 92 x 92 x 25 mm
3.62 x 3.62 x 0.98 in
Speed 300 – 2,500 rpm (regulated via PWM)
Noise Level 7.2 – 31.07 dBA
Air Flow 6.7 – 55.55 CFM
Bearing Type Sleeve Bearing

Gelid Silent Spirit: PHYSICAL DETAILS

The Silent Spirit features 4 copper heatpipes and 43 aluminum
fins. It measures 111 mm high on the short side, 127 mm on the tall side, and
weighs approximately 350 grams, 280 grams without the fan.


The Silent Spirit’s heatpipes and mass of fins are tilted upward at a
10 degree angle. The fan is suspended more than 1 cm above the surface
of the heatsink.


There is a small tertiary heatsink sitting atop the base, a common feature
on Scythe heatsinks.


The fins at the very top have 9 pairs of ribs that extend further upward
than the rest. On average, the fins are 0.36 mm thick and spaced 1.77
mm apart. The overall mass is quite thin compared to most third party
coolers.


From underneath.


The heatpipes are connected to a flat, but rather dull copper base. There
is no solder visible connecting the two portions.

Scythe Samurai ZZ: PHYSICAL DETAILS

The Samurai ZZ features 3 copper heatpipes and 47 aluminum fins.
It stands 94 mm high, and weighs about 480 grams, 390 grams without the fan.


The Samurai ZZ also has a slight tilt, though it does not appear to be
intentional, simply slumping down at one side due to the weight.


The Samurai ZZ’s secondary heatsink is much wider than the Silent Spirit’s.


On average, the fins are 0.33 mm thick and spaced 1.74 mm apart.


From underneath.


The heatpipes are flattened and soldered to a flat nickel-plated base
with a decent finish.

INSTALLATION

The most critical aspect of installation is for the heatsink to
be securely mounted. The more firmly it is installed, the better the contact
between the heatsink’s base and the CPU itself. It’s also less likely to fall
off. Ease of installation is also important — a simple mounting scheme
means less time spent installing, and reduced likelihood of user error.

Gelid Silent Spirit:


The mounting clips are attached using a pair of screws, one on
each side of the base.


On AMD platforms, the heatpipes run parallel to the expansion slots.

Scythe Samurai ZZ:


Installation on the Samurai ZZ is dead simple as well. The appropriate
clips snap into a pair of grooves on each side.


The AMD clips are spring-loaded and have to be engaged on both sides,
resulting in a very secure mount. The heatsink overhangs the memory slots
on our board if positioned in the opposite orientation to the one pictured
above.

TESTING

Before thermal testing, we took some basic physical measurements.

Approximate Physical Measurements
Heatsink Gelid Silent Spirit Scythe Samurai ZZ
Weight
280 g
350 g with fan
390 g
480 g with fan
Fin count 43 47
Fin thickness
0.36 mm 0.33 mm
Fin spacing
1.77 mm 1.74 mm
Vertical Clearance*
53 mm 35 mm
Horizontal Overhang**
-23 mm
+4 mm (AMD mounting clips)
-21 mm
* measured from the motherboard PCB to
the bottom fin of the heatsink.
** measured from the far edge of the heatsink to the top edge of the motherboard
PCB.

 

Comparison: Approximate Fin Thickness & Spacing
Heatsink
Fin Thickness
Fin Spacing
Scythe Big Shuriken
0.33 mm
1.19 mm
Scythe Samurai ZZ
0.33 mm
1.74 mm
Gelid Silent Spirit
0.36 mm
1.77 mm
Xigmatek HDT-SD964
0.38 mm
1.86 mm
Scythe Ninja Mini
0.42 mm
3.46 mm

Testing was done on our new
AM3 heatsink testing platform for small and low-profile heatsinks
. A
summary of the test system and procedure follows.

Key Components in Heatsink Test Platform:

  • AMD Athlon II X4 630 AM3,
    2.8GHz, 45nm, 95W TDP.
  • Asus M4A785TD-V EVO ATX motherboard.
    785G chipset.
  • Kingston
    SSDNow V
    30GB 2.5″ solid-state drive. Chosen for silence.
  • 2GB
    Corsair Dominator
    DDR3 memory. 2 x 1GB DDR3-1800 in dual channel.
  • FSP Zen 300W
    ATX power supply. Fanless.
  • Arctic Silver
    Lumière
    : Special fast-curing thermal interface material, designed
    specifically for test labs.
  • Nexus 92 fan (part of our standard testing methodology; used when
    possible with heatsinks that fit 92x25mm fans)

With a fanless power supply and a solid state drive, the test system is silent
under the test conditions, except for the CPU cooling fan(s). At full load,
the total system power draw is 132~140W AC, with the CPU and VRMs drawing 85~91W
DC (measured at the AUX12V connector), depending on their respective temperatures.

Smaller Heatsink Test Platform:
Full Load Power Details
System
132-140W AC
CPU+VRM
85~91W DC

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

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.
  • CPUBurn,
    used to stress the CPU heavily, generating more heat than most real applications.
  • 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 CPUBurn 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 stock fan was 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.

TEST RESULTS

Stock Fan Measurements: Gelid Silent Spirit

Stock Fan Specifications
Manufacturer
Power Rating
2.76 W
Model Number
G12922524(M)-P
Airflow Rating
48.5 CFM
Bearing Type
Hydro Dynamic
Speed Rating
900~2400 RPM
Corners
N/A
Noise Rating
10~25.8 dBA
Frame Size
101 x 101 x 40 mm
Header Type
4-pin PWM
Fan Blade Diameter
87 mm
Starting Voltage
3.4 V
Hub Size
36 mm
Weight
70 g
Data in green cells provided by the manufacturer
or observed; data in the blue cells were measured.

The Silent Spirit’s stock fan is a clone of those used by Arctic Cooling, a
7-blade model with fluid bearings, minimal housing, soft-mounted to a plastic
frame that clips onto the heatsink. The fan can start with as little as 3.4V,
which is atypical for a PWM model.

Stock Fan Measurements
Voltage
Speed
SPL @1m
12V
2470 RPM
32 dBA
9V
2030 RPM
26 dBA
7V
1750 RPM
20 dBA
6V
1470 RPM
15~16 dBA
5V
1060 RPM
12 dBA
Measuring mic positioned 1m at diagonal angle from
the intake side of the fan.
Ambient noise level: 11 dBA.

Acoustically speaking, the stock fan is fairly good. It is turbulent, buzzy,
and generates a hum at 9V~12V. The hum disappears at 7V, and the character becomes
mostly smooth. It is quiet at 6V with a slight rattle audible up-close. At 5V,
it is practically inaudible.

Stock Fan Measurements: Scythe Samurai ZZ

Stock Fan Specifications
Manufacturer
Power Rating
2.04 W
Model Number
SY9225SL12M-P
Airflow Rating
6.7~55.55 CFM
Bearing Type
Sleeve
RPM Rating
300~2500 RPM
Corners
Open
Noise Rating
10~25.8 dBA
Frame Size
92 x 92 x 25 mm
Header Type
4-pin PWM
Fan Blade Diameter
86 mm
Starting Voltage
6.8 V
Hub Size
33 mm
Weight
90 g
Data in green cells provided by the manufacturer
or observed; data in the blue cells were measured.

The Scythe fan is a Slip Stream, though their 92 mm variants have fewer blades
and less curvature.

Stock Fan Measurements
Voltage
Speed
SPL@1m
Free Air
Mounted
12V
2440 RPM
26~27 dBA
34~35 dBA
10V
2080 RPM
22 dBA
29~30 dBA
9V
1810 RPM
17~18 dBA
25 dBA
8V
1460 RPM
13~14 dBA
18 dBA
7.7V
1300 RPM
13 dBA
15 dBA
7.5V
940 RPM
<11 dBA
<11 dBA
Measuring mic positioned 1m at diagonal angle from
the intake side of the fan.
Ambient noise level: 11 dBA.

Like other Slip Streams, this 92 mm variant is very smooth, but buzzy at 9V
and higher. Oddly, the fan is significantly louder when mounted on the heatsink
than in free air, measuring about 7 dBA higher when the fan is set to 9V or
higher. Thankfully the difference is much less at lower fan speeds, 3~4 dBA
at 8V, and only 2 dBA at 7.7V. At 7.5V and below, the fan is inaudible in both
scenarios.

The Scythe Katana 3, a
slanted but mostly upright cooler, is equipped with the same fan model and fan
clips but the noise difference was much smaller when we tested it. The increase
in noise on the Samurai ZZ is mostly turbulent, and likely caused by the air
bouncing off the motherboard. Taller downblowing coolers don’t seem to be affected
by this phenomenon.

COOLING RESULTS

Note that these heatsinks were tested on our new AM3 test platform. An Athlon
II X4 630 with 95W TDP is the processor. The CPU/VRMs on our new platform draw
between 85W and 91W DC (depending on temperature) at the AUX12V connector, slightly
more than the problematic LGA775/Pentium D950 set up we had been using in the
past. For full details, please see Postscript 2 of SPCR’s 2010 CPU
Heatsink Test Platform
on the new
AM3 heatsink testing platform for small and low-profile heatsinks

Gelid Silent Spirit w/ stock fan
Fan Voltage
SPL@1m
Temp
°C Rise
12V
32 dBA
44°C
21
9V
26 dBA
45°C
22
7V
20 dBA
48°C
25
6V
15~16 dBA
58°C
35
5V
12 dBA
76°C
53
Gelid Silent Spirit w/ ref. 92 mm fan
12V
16 dBA
53°C
30
9V
12 dBA
59°C
36
°C Rise: Temperature rise above ambient (23°C)
at load.

The Silent Spirit with its padded and frameless stock fan delivered very good
performance at 9V and 12V with a thermal rise over ambient of just above 20°C.
The CPU heated up by 3°C at 7V and at 6V there was an additional 10°C
jump. It’s effectiveness weakened dramatically as the fan speed was reduced
to quiet levels. At 5V, the temperature climbed 18°C higher than at 6V.

Our reference Nexus fan performed 5°C better at 12V/16 dBA compared to
the stock fan at 6V/15~16 dBA. At the 12 dBA level, the Nexus crushed the stock
fan by an unbelievable 17°C. Note that the Nexus was placed flat on the
heatsink without any support. Swapping the fan in this manner in a real-life
scenario would require an alternate method to secure the fan, such as twist-ties.

Scythe Samurai ZZ w/ stock 92 mm fan
Fan Voltage
SPL@1m
Temp
°C Rise
12V
34-35 dBA
44°C
21
10V
29~30 dBA
46°C
23
9V
25 dBA
48°C
25
8V
18 dBA
52°C
29
7.7V
15 dBA
53°C
30
7.5V
<11 dBA
55°C
32
Scythe Samurai ZZ w/ ref. 92 mm fan
12V
16 dBA
48°C
25
9V
12 dBA
54°C
31
°C Rise: Temperature rise above ambient (23°C)
at load.

At higher fan speeds, the Samurai ZZ was comparable in performance to the Silent
Spirit, but generated a lot more noise, but at lower fan speeds, the Samurai
ZZ was far superior. At 8V/18 dBA, the thermal rise above ambient was 25°C.
This barely increased at 7.7V/15 dBA, and there was only a 3°C rise at 7.5V
even though the fan had become inaudible. The Samurai ZZ performs superbly with
very limited airflow.

Our reference Nexus fan attained the same thermal rise at 12V/16 dBA as the
stock fan at 9V/25 dBA. At 9V it was slightly louder than the stock fan at 7.5V,
but 1°C better, making it wash at that level.

Comparison Tables

°C rise Comparison (stock fan)
SPL@1m
HDT-SD964
Samurai ZZ
Big Shuriken
Arctic Alpine 64
Silent Spirit
18 dBA
29
17 dBA
34
16 dBA
30
35
15 dBA
22
30
43
14 dBA
13 dBA
27
12 dBA
34
46
53
11 dBA
37
<11 dBA
32

Paired with its stock fan, the Samurai ZZ’s greatest asset is its amazing performance
at lower fan speeds. When operating at fan speeds that generate 18 dBA@1m or
less, its cooling proficiency barely changed. So while it may be a poorer heatsink
than a 92 mm tower cooler like the Xigmatek
HDT-SD964
at higher fan speeds, for ultra quiet operation, the Samurai
ZZ is the better choice.

The Silent Spirit is a few degrees behind the Samurai ZZ and Big
Shuriken
at the 15~16 dBA level, but at 12 dBA, its performance drops
to the point where it is beaten handily by the Arctic Alpine 64, which incidentally,
can be purchased online for as little as US$10.

°C rise Comparison (reference fan)
Heatsink
Nexus 92 mm fan voltage / SPL@1m
12V
9V
16 dBA
12 dBA
Scythe Ninja Mini
23
27
Xigmatek HDT-SD964
24
30
Scythe Samurai ZZ
25
31
Scythe Big Shuriken
(Nexus 120 mm fan)
24
(12V)
33
(7V)
Gelid Silent Spirit
30
36

Using our reference Nexus fan seems to make things a little more even, but
the Samurai ZZ still holds a substantial lead over the Silent Spirit, and is
only 1°C off the performance of the HDT-SD964.

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.

FINAL THOUGHTS

Gelid Silent Spirit

The Gelid Silent Spirit is certainly a quiet CPU cooler thanks to a smooth-sounding,
frameless fluid bearing fan, the mechancally decoupled isolation from the heatsink,
and the fact that it sits more than 1 cm away from the surface of the heatsink.
The fan blades’ distance from the fins and the relatively small fin area limits
its cooling capabilities, though, particularly when the fan speed is slowed
down. At the 15~16 dBA level, our reference Nexus 92 mm fan beat the stock fan
by 5°C, but at 12 dBA (close to inaudible) it was absolutely destroyed to
the tune of 17°C. It seems to us that all the effort invested into limiting
the amount of noise generated by the stock fan would have been better spent
in simply finding a good fan with a standard box housing. Still, even with the
reference fan, the Silent Spirit ran about 5°C hotter than the Samurai ZZ.
Both coolers can be found for as low as US$30, but the Silent Spirit appears
to be inferior in every way.

Gelid Silent Spirit
PROS

* Good medium to high airflow performance
* Stock fan has good acoustics

CONS

* Poor low airflow performance with stock fan
* No LGA1156 or 1366 mounting clip included
* Poor value given the cost

Scythe Samurai ZZ

Though the design of the Scythe Samurai ZZ makes its excellent fan noisier
than in free air, its performance was still superb. It cooled our Athlon II
X4 CPU well when the fan was set to produce 18@1m dBA, but its resiliency as
the fan speed was reduced was far more impressive. The CPU temperature increased
by only 3°C when the fan was slowed to an inaudible level. When paired with
our reference fan, it became even stronger, making it competitive with smaller
tower coolers like the Xigmatek
HDT-SD964
. If you’re in the market for a modestly-sized downblowing
CPU cooler, the Samurai ZZ should definitely be on your short-list.

Scythe Samurai ZZ
PROS

* Good high airflow performance
* Excellent low airflow performance
* Stock fan has good acoustics
* Full socket compatibility

CONS

??

Our thanks to Gelid
Solutions
and Scythe
Co., Ltd.
for the Silent Spirit and Samurai ZZ heatsink
samples.

* * *

Articles of Related Interest


Scythe Grand Kama Cross CPU
Cooler

Titan Fenrir & Coolermaster Hyper
212 Plus: Direct Touch Revisited

Corsair Hydro H50 CPU Water Cooler
Prolimatech Armageddon & Coolermaster
V8 CPU Coolers

Cogage TRUE Spirit
& Zalman CNPS10X Quiet CPU Coolers

SPCR’s 2010 CPU Heatsink
Test Platform

* * *

Discuss
this article in the SPCR forums.

Silent PC Review is reader-supported. When you buy through links on our site, we may earn an affiliate commission. Learn More

Leave a Comment

Your email address will not be published. Required fields are marked *