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Antec EarthWatts 430: Green Computing Hits Mainstream

October 30, 2006 by Devon
Cooke

Product
Antec Earth Watts 430
EA-430

80 Plus Certified ATX12V v2.2 compliant power supply
Manufacturer
Antec
MSRP
430: US$79.95;

380: US$64.95;

500: US$99.95

Efficiency has always been an important feature of good quality power supplies,
but, thanks to the development of the
80 Plus program
— and the publicity and marketing opportunities it
makes possible — there is now a market niche devoted solely to efficient
power supplies. At least, that seems to be what power supply sellers, Antec
among them, are hoping. Antec helped get the bandwagon rolling with the
Neo HE, released in late 2005
, and now they've come back to the table with
a model that promises to be even more efficient: The Earth Watts series.

In the year since the release of the Neo HE, Antec has done their homework
and realized that efficient power supplies appeal to a formerly unrecognized
market segment: Green computing. Now you can discuss
the health merits of banning trans fats
, help
research obscure proteins in the name of science
, and save the environment
at the same time! Well... perhaps things are a little more complicated than
that, but the Earth Watts is definitely designed to appeal to those who use
their computer for all that is good and right (and I'm not talking about joining
the Alliance in World of Warcraft).

The Earth Watts is not the first "environmentally-friendly" power
supply we've looked at. FSP's
Green PS
also purported to be good for the environment — mainly by
complying with RoHS before all of the cool kids started doing it. Despite
its environmental pretensions, the Earth Watts doesn't even mention RoHS in
its marketing — RoHS is now required in the EU, so it no longer anything
special.

Instead, the Earth Watts uses its efficiency — it's 80 Plus certified
— and the fact that it has active power factor correction to support its
claim to being Green. There's no question that both of these can help reduce
power costs, but they don't set the Earth Watts apart as much as you might think.
Other high end power supplies also boast these features, and the development
of efficiency as a selling point should mean that more 80 Plus power supplies
will be seen in the future.

APPEARANCES

The Earth Watts is packaged in a serene, nature-themed box that is in keeping
with the environmental theme of the power supply itself. It's slick — but
it doesn't send quite the same message as the plain, unbleached cardboard box
that the FSP Green PS came in.



Clean greens and blues suggest purity and tranquility in the environment.



No extras to speak of.

Inside the box, the selection of extras is spare, with nothing
above and beyond the essentials necessary for using the power supply. The power
supply is protected by two recycled cardboard ends that are probably better
for the environment than plastic bubble wrap — the most common packing
material. It's worth noting that Antec's other power supplies come packed in
a similar way.

FEATURE HIGHLIGHTS

Antec Earth Watts EA-430 Feature Highlights (from
Antec's
web site)
FEATURE & BRIEF COMMENT
80mm low noise cooling fan
Low noise to the standard
set by the Neo HE?
Dual 12V outputs:
12V2 for Motherboard and peripherals; 12V1 for processor
As required by ATX12V
2.0.
Industrial-grade protection circuitry prevents damage resulting from
short circuits, power overloads, over voltage, and
under voltage
The usual protection
circuits
80 PLUS® certified Certified to be at least
80% efficient at 20% (86W), 50% (215W), and 100% (430W) output.
4 SATA connectors
Standard these days.
PCI-E connector: one for 380W and 430W, two for 500W
Also standard.
Safety approvals:
UL, CUL, FCC, TÜV, CE, CB, C-tick, CCC
Worthwhile.
Universal input Nice to have, but hardly
a deal-maker in most parts of the world.
Active Power Factor Correction (PFC)
A boost converter to maintain a constant DC bus voltage while drawing a current always in phase with and at the same frequency as the line voltage. Benefits for AC power delivery; reduces input AC current
and can allow a smaller UPS to be used.
PF value up to 99% See comment on active
PFC above.
AQ3 Antec Quality three-year
parts and labor warranty
Antec's customer service
seems generally well-regarded.

SPECIFICATIONS

OUTPUT SPECIFICATIONS: Antec Earth Watts 430
AC Input
100-240V ~7A; 50/60 Hz
DC Output
+3.3V
+5V
+12V1
+12V2
-12V
+5VSB
Maximum Output Current
20A
20A
17A
17A
0.8A
2.5A
Minimum Output Current
0.3A
0.5A
1A
1A
0A
0A

Maximum Combined

130W
360W
9.6W
12.5W
430W

The 360W combined rating for the +12V rails is the most important specification,
and it should provide enough power for just about any system that can be built
with the available cable sets. With only one PCIe connector and no support for
dual CPU systems, it will be difficult if not impossible to overload the Earth
Watts.

The secondary lines are a little weaker than usual, although the 20A supplied
on each of them is still far in excess of what a modern system requires. However,
it is conceivable that a very powerful older system that draws CPU power from
the +5V line might cause a bit of a struggle, especially given the minimum load
requirements on both the +12V lines.

EXTERNAL TOUR

The unfinished exterior of the Earth Watts is unusual for a brand name power
supply, but the bare steel appearance bolsters the sense of being environmentally
friendly. Paint is not exactly good for the environment, and it's hardly necessary
on a piece of equipment that is not meant to be seen. On the other hand, even
"unfinished" steel has been treated with an anti-corrosive agent,
so it's not clear how much the lack of paint benefits the environment.

Aside from the finish, the exterior casing seems to have been taken from the
Neo HE. Most of the air is designed to flow in through the inner panel of the
power supply, not the bottom as is the case with the conventional 120mm fan.
The back panel is stamped full of square holes that provide ample space for
air to flow. There is also a smallish vent on one side that provides spot cooling
for a small secondary PCB.



Straight-through airflow makes the Earth Watts a good choice for building
a PSU duct.

Airflow is generated by a single 80mm fan that blows directly out the back
of the power supply. It is guarded by a wire grill that provides a good balance
between safety and open airflow. The straight-through airflow design of the
Earth Watts is somewhat uncommon these days, and is not designed to help with
CPU cooling as units with bottom-mounted fans are. That said, many silencers
prefer this style of airflow, as the layout makes it easy to duct fresh air
directly to the power supply — allowing the fan to spin more slowly under
load.



Cooling is provided by an 80mm fan.

FAN



The fan comes from well-known manufacturer, Adda.

The fan is a high speed, sleeve bearing model from Adda. Adda makes the fans
found in many of the quietest power supplies we know of, including Antec's own
Neo HE, so we have hopes that the Earth Watts will be a quiet performer. However,
the fan is not identical to the one in the Neo HE, which used a medium
speed, ball bearing fan. A direct comparison between the two will be instructive...

CABLES AND CONNECTORS

There are a total of seven cable sets:

  • 19" cable for main 24-pin ATX connector — sleeved in black &
    red vinyl
  • 19" cable for AUX12V 4-pin
  • 19" cable for 6-pin PCIe connector
  • 33" cable with three 4-pin IDE drive connectors
  • 38" cable with three 4-pin IDE drive connectors and one floppy connector
  • 2 x 27" cables with two SATA drive connectors

Cables are not especially long or short, and while some people may have difficulties
in larger cases, most people should be fine.

Users who consider appearance important (if any are still reading after seeing
the unfinished exterior) will be disappointed that only the main ATX cable is
sleeved. Given the environmental focus of the Earth Watts, we shouldn't expect
much in the way of bling though — it's designed for a different crowd.

Gamers will want to take note that only the 500W model comes with two PCIe
connectors. The two lower-end models come with only one. We hope that most readers
will appreciate the irony of providing these high power plugs in a "Green"
power supply — nobody with an interest in conserving power should choose
a graphics card that is power hungry enough to require one of these connectors.

INTERIOR

Inside the Earth Watts is a surprisingly sparse PCB cooled by surprisingly
small heatsinks. Knowing that this PSU is made by Seasonic, whose PSUs usually have fairly hefty heatsinks, this was especially surprising. The Seasonic-sourced Neo HE series have considerably more substantial heatsinks, for example. They're not quite as small as the heatsinks found in FSP's
Green PS
, but they may have been inspired by it. Presumably, what is lost
in heatsink area is supposed to be compensated by a lack of airflow impedance
— but we'll see how things work in practice. [Editor's Note: The reduced HS size and slightly higher speed might be considered part of a greener approach, a desire to use less material — aluminum in this case.]



Much of the PCB is visible thanks to smallish heatsinks that provide plenty
of room for airflow.



The heatsinks divide the interior neatly into separate channels.

The wisdom of the small secondary vent in the external casing becomes apparent
by examining where it is located. The position of the fan means that most of
the airflow will be drawn between the two outer heatsinks, leaving the rightmost
third of the power supply with only a little residual airflow. Additionally,
the large bundle of wires mean that this portion of the power supply has less
intake area than the rest of the power supply.

The Earth Watts deals with this in two ways. First, most of the heat sensitive
components are located centrally, where there is plenty of airflow. The output
wires may block airflow, but they don't require much cooling compared to the
major electronic components. Second, the secondary vent provides a little extra
airflow that is directed over a small secondary PCB just in front of it. This
PCB is visible in the bottom section of the photo below.



This side is away from the fan, and is less well cooled than the rest.

Fortunately, it's mostly wires, and the secondary vent provides a little extra
airflow.

TESTING

For a fuller understanding of ATX power supplies, please read the reference
article Power Supply Fundamentals & Recommended
Units
. Those who seek source materials can find Intel's various PSU
design guides at Form
Factors
.

For a complete rundown of testing equipment and procedures, please refer to
SPCR's PSU Test Platform
V.4
. The testing system is a close simulation of a moderate airflow
mid-tower PC optimized for low noise.

In the test rig, the ambient temperature of the PSU varies proportionately
with its output load, which is exactly the way it is in a real PC environment.
But there is the added benefit of a high power load tester which allows incremental
load testing all the way to full power for any non-industrial PC power supply.
Both fan noise and voltage are measured at various standard loads. It is, in
general, a very demanding test, as the operating ambient temperature of the
PSU often reaches >40°C at full power. This is impossible to achieve
with an open test bench setup.

Great effort has been made to devise as realistic an operating
environment for the PSU as possible, but the thermal and noise results obtained
here still cannot be considered absolute. There are too many variables in PCs
and too many possible combinations of components for any single test environment
to provide infallible results. And there is always the bugaboo of sample variance.
These results are akin to a resume, a few detailed photographs, and some short
sound bites of someone you've never met. You'll probably get a pretty good overall
representation, but it is not quite the same as an extended meeting in person.

REAL SYSTEM POWER NEEDS: While our testing loads the PSU to full output
(even >600W!) in order to verify the manufacturer's claims, real desktop
PCs simply do not require anywhere near this level of power. The most pertinent
range of DC output power is between about 65W and 250W, because it is the power
range where most systems will be working most of the time. To illustrate this
point, we conducted system tests
to measure the maximum power draw that an actual system can draw
under worst-case conditions.
Our most power-hungry Intel 670 (P4-3.8) processor
rig with nVidia 6800GT video card drew ~214W DC from the power supply under
full load — well within the capabilities of any modern power supply. Please
follow the link provided above to see the details. It is true that very elaborate
systems with the most power hungry video card today could draw as much as another 60~100W, but the total
still remains well under 400W in extrapolations of our real world measurements. As for high end dual video card gaming rigs... well, to be realistic, they have no place in silent computing today.

SPCR's high fidelity sound
recording system
was used to create MP3 sound files of this PSU. As
with the setup for recording fans, the position of the mic was 3" from the exhaust
vent at a 45° angle, outside the airflow turbulence area. The photo below shows
the setup (a different PSU is being recorded). All other noise sources in the
room were turned off while making the sound recordings.

INTERPRETING TEMPERATURE DATA

It important to keep in mind that fan speed varies with temperature,
not output load. A power supply generates more heat as output increases, but
is not the only the only factor that affects fan speed. Ambient temperature
and case airflow have almost as much effect. Our test rig represents a challenging
thermal situation for a power supply: A large portion of the heat generated
inside the case must be exhausted through the power supply, which causes a corresponding
increase in fan speed.

When examining thermal data, the most important indicator of cooling efficiency
is the difference between intake and exhaust. Because the heat
generated in the PSU loader by the output of the PSU is always the same for
a given power level, the intake temperature should be roughly the same between
different tests. The only external variable is the ambient room temperature.
The temperature of the exhaust air from the PSU is affected by several factors:

  • Intake temperature (determined by ambient temperature and power output level)
  • Efficiency of the PSU (how much heat it generates while producing the required
    output)
  • The effectiveness of the PSU's cooling system, which is comprised of:
    • Overall mechanical and airflow design
    • Size, shape and overall surface area of heatsinks
    • Fan(s) and fan speed control circuit

The thermal rise in the power supply is really the only indicator
we have about all of the above. This is why the intake temperature is important:
It represents the ambient temperature around the power supply itself. Subtracting
the intake temperature from the exhaust temperature gives a reasonable gauge
of the effectiveness of the power supply's cooling system. This is the only
temperature number that is comparable between different reviews, as it is unaffected
by the ambient temperature.

TEST RESULTS

Ambient conditions during testing were 21°C and 19 dBA. AC input was 117V,
60Hz.

OUTPUT & EFFICIENCY: Antec Earth Watts 430











DC Output Voltage (V) + Current (A)

Total DC Output

AC Input

Calculated Efficiency
+12V1
+12V2
+5V
+3.3V
-12V
+5VSB
12.07
0.96
12.06
1.73
4.99
0.97
3.31
0.96
0.1
0.2
42.7
60
70.8%
12.10
1.91
12.10
1.73
4.98
1.92
3.31
2.74
0.1
0.4
65.9
87
75.6%
12.11
1.89
12.09
3.44
4.98
2.84
3.32
2.69
0.2
0.5
92.5
118
78.3%
12.04
3.74
12.02
4.96
4.95
4.57
3.32
4.58
0.3
0.9
150.6
186
81.0%
12.02
5.57
11.99
6.42
4.95
5.44
3.32
5.37
0.4
1.2
199.5
239
83.5%
11.99
7.71
11.96
8.06
4.94
6.32
3.32
5.32
0.5
1.5
251.2
302
83.2%
11.99
8.65
11.95
9.73
4.94
7.93
3.31
7.56
0.6
1.7
299.9
364
82.4%
11.94
13.03
11.90
12.56
4.91
11.99
3.33
13.27
0.8
2.5
430.2
548
78.5%
Crossload Test
11.59
14.63
11.54
15.14
5.07
1.94
3.32
1.88
0.0
0.0
360.4
449
80.3%
+12V Ripple: 3.0 mV @ 150W ~ 4.6 mV @ 360W (Crossload
Test)

+5V Ripple: 3.0 mV @ 150-200W ~ 3.8 mV @ 430W

+3.3V Ripple: 2.5 mV @ 150-250W ~ 3.4 mV @ 40W
NOTE: The current and voltage for -12V and
+5VSB lines is not measured but based on switch settings of the DBS-2100
PS Loader. It is a tiny portion of the total, and potential errors arising
from inaccuracies on these lines is


OTHER DATA SUMMARY: Antec Earth Watts 430
DC Output (W)
42.0
65.9
92.5
150.6
199.5
251.2
299.9
430.2
Intake Temp (°C)
21
21
22
29
30
33
35
38
Exhaust Temp (°C)
26
26
28
35
37
38
42
50
Temp Rise (°C)
5
5
6
6
7
5
7
12
Fan Voltage (V)
4.2
4.3
4.3
4.3
4.4
6.0
8.4
11.1
SPL ([email protected])
22
22
22
22
24
29
37
43
Power Factor
0.99
0.99
1.00
1.00
0.99
0.99
0.99
1.00

AC Power in Standby: 0.4W / 0.11 PF

AC Power with No Load, PSU power On: 8.7W / 0.76 PF
NOTE: The ambient room temperature during
testing can vary a few degrees from review to review. Please take this
into account when comparing PSU test data.

ANALYSIS

1. EFFICIENCY was excellent, as we expected of an 80 Plus certified
unit. However, we were a little surprised that it missed the 80% mark at both
20% and 100% load. To be sure, it didn't miss by much, but it was a surprise
nonetheless. A second sample that we tested proved to have similar efficiency.

2. VOLTAGE REGULATION was excellent; by our usual tests, none of the
lines fluctuated by more than 2%, and the +12V and +3.3V lines were within 1%
of nominal throughout the test.

Things got more interesting when we tried our Crossload Test: Full load on
the +12V lines (30A) and a token 2A on each of the +5V and +3.3V lines. This is a
new test, and is designed to push the voltage regulation to its limits and better
simulate the kind of unbalanced load that a real system might to have. The
Earth Watts had no problem staying within spec though — the +12V line regulation
sagged to -4% of nominal, and the +5V line jumped up to its highest level
during the test. The +3.3V line did not appear to be affected by the cross loading,
and stayed unchanged at 3.32V.

3. RIPPLE

Ripple was also tested, and remained uniformly excellent under every condition
that was tested. The worst ripple occurred during the cross loading when the
+12V ripple peaked at 4.6 mV. To put that in perspective, the ATX12V requires
+12V ripple to be below 120 mV. The Earth Watts has more than a little headroom
in this respect. Ripple on the other lines was similarly low, and fluctuated
very little no matter how the power supply was loaded.



+12V ripple (left) was ~3.0 mV, and +5V (right) ripple was ~3.0mV, both measured
at 150W.



+3.3V ripple at 150W output was ~2.5 mV.

4. POWER FACTOR was excellent thanks to the active power factor correction
circuit, staying very close to the theoretical maximum of 1.0.

5. LOW LOAD PERFORMANCE

Standby and no-load performance were both reasonably efficient, with standby
coming in well under one watt, and no-load at a little under ten. The Earth
Watts had no issues starting or staying on with no load applied.

6. LOW AC VOLTAGE PERFORMANCE

The power supply was set to about 75% load with 120VAC through the hefty variac in the lab. The dial on the variac was then set 10V lower every 10 minutes. Since most power supplies are only rated for operation at 100~240VAC, our test calls for a minimum input voltage of 90VAC. However, in this case, we pushed it down to 80VAC.

Low AC Voltage Test: Antec Earth Watts 430 @ 326W Output
AC Input
AC Current
AC Power
Efficiency
+12V
+5V
+3.3V
120V
3.25A
398W
82.0%
11.97
4.97
3.34
110V
3.66A
401W
81.3%
11.98
4.97
3.34
100V
4.00A
405W
80.5%
11.97
4.97
3.34
90V
4.53A
410W
79.5%
11.97
4.97
3.35

80V

5.16A

417W

78.2%

11.97

4.97

3.37

The Earth Watts stood up to the drops in AC voltage admirably, even when operating
well below its rated input voltage of 100V. Neither voltage regulation nor ripple
changed measurably during the test, and efficiency dropped only marginally under the most severe conditions.

I must admit that the adolescent boy in me was a little disappointed when the
Earth Watts showed no visible stress in this test. The
last time we played with low AC voltages
we had some fireworks: One unit
shut down as soon at the voltage dropped to 100V; another sparked and failed
entirely!

To be fair, these earlier tests were done at 100% load, but we were pleased
to find that the Earth Watts was quite happy to keep running indefinitely even
with the voltage dropped to 80V!

7. TEMPERATURE & COOLING

Thermal results were acceptable, despite the smaller heatsinks. The thermal
rise through the unit remained at roughly 6°C through all of the tests except
for full load when it jumped up to about 12°C. Given that the exhaust temperature
only barely reached the maximum operating temperature, it seems safe to say
that the Earth Watts is well cooled.

One word of warning: Due to recent changes in our test bench, thermal results
are not directly comparable to earlier tests that we have done. Our new test
bench uses a larger 120mm fan that provides a more realistic simulation of the
kinds of low-noise systems that are in use today.

8. FAN, FAN CONTROLLER and NOISE

As any change to airflow also affects noise, the same caveat applies to our
noise results; noise results for the Earth Watts are not comparable to earlier
reviews. We do not believe that the change is large, but the larger fan will
certainly have an effect; the increase in airflow can be expected to delay the
point when the fan increases in speed. Cooler temperatures inside the test bench
mean that the power supply doesn't have to work as hard to keep cool, and it
can therefore run more quietly Another possible point of change is the fact
that the larger fan may let out more noise than previously.

Although the Earth Watts has almost the same starting voltage as the Neo HE,
it was slightly but audibly louder at minimum speed. Most significantly, it
produced a low hum that was absent in the Neo HE. The measured difference may
only have been 2 [email protected], but the subjective difference was easy to notice. That's
not to say that the Earth Watts was loud, exactly, but it didn't quite fall
into the "practically inaudible" category that made the Neo HE so
special.

The fan controller in the Earth Watts was quite good, remaining at minimum
until approximately ~200W output and remaining reasonably quiet even at 250W.
Gaming systems may be able to stress the power supply enough to push the fan
up above this, but most systems should have no problem staying within a 200W
envelope. However, once the fan had started to change speed, it proved to be
fairly sensitive, and changes in fan speed occasionally drew attention to themselves.

MP3 SOUND RECORDINGS

Each of these recording have 10 seconds of silence to let you hear the ambient
sound of the room, followed by 10 seconds of the product's noise.

Sound Recordings of PSU Comparatives

HOW TO LISTEN & COMPARE

These recordings were made
with a high resolution, studio quality, digital recording system, 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. Two recordings of each noise level were made, one from a
distance of one meter, and another from one foot
away.

The one meter recording
is intended to give you an idea of how the subject of this review sound
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. For best results, set your volume control so that the
ambient noise is just barely audible. 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 one foot recording is
designed to bring out the fine details of the noise. Use this recording
with caution! Although more detailed, it may not represent how the subject
sounds in actual use. It is best to listen to this recording after you
have listened to the one meter recording.

More details about how
we make these recordings can be found in our short article: Audio
Recording Methods Revised
.

CONCLUSIONS

The Earth Watts may be aimed squarely at the (emerging?) Green computing market,
and worthy of praise on other merits. It's highly
efficient thanks to an 80 Plus certified design, it has excellent electronics
(as demonstrated by our rigorous electrical tests), and it's pretty quiet
too. Pricing is also very good for a good quality power supply. There's much to like here, and very little to dislike.

Still, we're not really sold on the "Green" aspects of the Earth Watts.
High efficiency, active PFC, and the required RoHS compliance all make good
selling points for the Green conscious, but these features are not unique
to the Earth Watts — all of these are hallmarks of good quality power supplies,
"Green" or not. And how much impact does the extra efficiency
have, anyway? We're all for efficiency and being environmental friendliness, but
we find it hard to believe that the energy saved by the extra efficiency is
all that great, especially at the 40~60W level that a well-designed system should
idle at. The 6~8W difference between 60% and 70% efficiency at this level just
doesn't seem like much. It's certainly not enough to justify buying a replacement
power supply if the environment has to bear the cost of putting the old power
supply in a landfill.

On the other hand, if you're in the market for a new power supply, and
your needs run towards the thrifty and the efficient rather than the flashy
and the powerful, the Earth Watts may be one of the best there is. To our knowledge,
the 380W model is the smallest 80 Plus certified power supply on the retail
market at the moment.

So, of Antec's two "efficient" PSU models (the Neo HE and the Earth
Watts), which would we choose? That's a tough question because it depends on
your priorities. There's no doubt that the Earth Watts is the more efficient
of the two, but it's equally clear that the Neo HE has less residual noise.
This being Silent PC Review, we'd lean towards the Neo HE, especially
for lower power systems where the lower efficiency is less significant and the
fan is unlikely to ramp up. For more powerful systems, the choice is less clear:
Do you go with the lower residual noise of the Neo HE, or do you get the Earth
Watts so that the fan is quieter when the system is under load? Much depends
on how noisy the rest of the system is.

The Earth Watts seems best suited to systems where absolute silence
is not the goal. It's quiet enough for general use, especially in mid-range
gaming systems where the graphics card is likely to drown out any noise from
the power supply unless the fan ramps up. Extreme silencers may prefer a Neo
HE, and high-end enthusiasts will no doubt want one of Seasonic's designer power
supplies, but the Earth Watts seems like a good quality mainstream choice.

*

SPCR Articles of Related Interest:

Power Supply Fundamentals & Recommended
Units


Power Distribution within Six PCs

SPCR PSU Test Rig V.4


FSP Green PS

Seasonic S12 Energy Plus

Antec NeoHE 430

Silverstone Element Plus ST50EF-Plus

* * *

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this article in the SPCR Forums.

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