Antec NSK-3480: 80-Plus Case

Antec has updated its popular NSK-3300 with a new power supply and some tweaks to airflow and cable management. The power supply is its 80-Plus EarthWatts, making the NSK-3480 the first 80-Plus certified case on the market. Can Antec make a good thing better?

October 21, 2007 by Devon
Cooke

In recent years, Antec has built an extensive, popular lineup of computer
cases based around solid thermal and acoustic ideas. Multiple, independent thermal zones,
soft hard drive grommets, and wide-open air intakes are all invaluable for silencing,
and these features show up in Antec’s lineup frequently.

The NSK-3480 has all of these features, but it’s not really a new product.
It has evolved from the NSK-3300,
which we reviewed here a little over a year ago. Since then, is has evolved
through the NSK-3400 to its current version. In both cases, the biggest change
was not in the case itself but the power supply bundled with it:

• The NSK-3400
  switched the power supply from a small SFX12V model to the more common ATX12V
  standard, as well as tweaking the cable management.
• The NSK-3480 bumps the power
  supply up to a more efficient, 80-Plus
  certified model: An EarthWatts
  380.

The internal layout and airflow are almost
identical to the original, so we can expect most of the conclusions reached
in our review of the NSK-3300
to apply here as well. We strongly recommend reading the older review as well
as this one.

Yes, that is an 80-Plus logo on the lower right.

A quick once-over of the exterior appearance reveals only a couple of relevant
changes: An expanded top vent that allows the power supply to breath more easily,
plus the addition of a side CPU vent in accordance with Intel’s TAC (Thermally
Advantaged Chassis) guidelines.

The only visible difference from this angle is the expanded top vent.

A side vent for CPU cooling has also been added.
The change to an ATX power supply is also clearly visible.

AIRFLOW LAYOUT

Airflow is divided into two zones, one for the power supply, the other for
the rest of the system. The upper chamber is pysically separated from the low main chamber — an inverse of the P182, where the PSU is in a separate chamber on the bottom. The only other components that can go into the upper chamber are an optical drive and a
hard drive. This arrangement keeps heat from other components in the system from getting into the power supply. The PSU’s thermally controlled fan should not increase in speed unless the system is
placed under an exceptionally heavy load.

The upper chamber is completely separated from the main chamber.

This view shows the inside of the upper PSU chamber.

There are two intake airflow paths forv the power supply:

• The top vent (shown below), which has been expanded to five times its previous
  size.
• One of the optical drive bays, if it is left free, provides access to the vent inlets all around the circumference of the front bezel.

The top vent has been expanded to ensure the power supply is well cooled.

The increased vent openings on the top panel is a good thing, as the top chamber could potentially be very crowded.
However, it does mean that the case is vulnerable to having items placed on
top of it. It would not be hard to accidentally block the airflow by placing
a book or a newspaper on top of the vent.

Access to the interior requires no tools, as before: Remove the top panel by undoing two thumbscrews, then either of the side panels can be lifted up and off. The side ponels have locking bayonet mounts that use gravity and the top panel to keep them in place. It’s quick and simple.

The main chamber has changed very little. Airflow is provided by one of Antec’s
ubiquitous TriCool fans, and it is possible to install two 92mm fans in
the front panel. There is also a smallish vent on the rear panel, and all the
PCI slots are vented.

There is space for two 92mm fans in front, but most users won’t need them.

The only significant change in the main chamber is the addition of a side panel
duct above the CPU — as recommended by Intel — to provide fresh air
to the CPU. Given how open the case was already, it’s unlikely this will change
much, but it may be helpful in systems where the CPU is the hottest component.

On the whole, the case breathes very well; the fan grills are not restrictive, and the front bezel — one of the best aspects of the original
NSK-3300 design — has remained unchanged.

A side panel duct to provide fresh air to the CPU.

OTHER CHANGES

Aside from the airflow tweaks, there are a couple other minor changes that
we spotted. One is the feet. Antec has apparently stopped using the squishy,
semitransparent silicone feet in the NSK-3480. Our sample came with black rubber
feet. The rubber is much harder than silicone but is still fairly soft for rubber.
In theory, the case may now be more prone to transferring vibration to the surface
it is placed on, but the situations where this is a problem are quite limited
in our experience, especially if the rest of the system is well built.

Hard rubber feet provide less vibration damping than before.

Another minor change was the addition of a grounding screw to the front panel
connectors. Presumably, this is to prevent ground faults between the front ports
(and power buttons) and the motherboard, which can sometimes cause things like
random restarts or burnt out switches. We’re not sure whether this was added
in response to a specific problem identified with the NSK-3300, but it certainly
can’t hurt.

The front panel connectors are now grounded to the side of the case.

CABLE MANAGEMENT

Antec has improved cable management by moving the access port between
the two chambers to the side, out of the way of tall heatsinks. The PSU output cables are longer and there are more of them than before. Two locking
straps to help route the cables down into the main chamber.

Cables now leave the top chamber along the side of the chamber.

A sliding plastic cover helps maintain the seal between the two chambers.

A secondary port just below the power supply is ideally suited for running
an IDE cable or two for the drives in the top chamber. A handsome rubber plug
is included to block the port when it is not in use.

A secondary port just in front of the PSU is ideally suited for flat IDE
cables.

A major criticism we had of the NSK-3300 was the limited number of short power
cables. This problem has now been fixed, but Antec may have gone a bit too far
in doing so; there are now so many cables that it is difficult to find space
for all the spares. The logical place to leave them is in the top chamber, but
there are so many that they block the front intake almost completely if there
is an optical drive installed. With a hard drive in place at the same time,
the cables would need to be routed out of the top chamber to prevent the power
supply from overheating.

In the main chamber, there are more options. If there are only one or two spare
cables, the locking strap on the plastic port cover might hold them, but there
is not enough clearance under the side panel for a lot. Our favorite solution
is shown in the photo below: The floppy bay is an ideal place to stuff spare
cables.

We put the unused output power cables in the floppy bay.

POWER SUPPLY

The biggest change is the switch from a small SFX12V power supply
to a full-sized, 80 Plus power supply. The change was made despite the very
short depth of the case, and the photo below shows just how little space is
left for drives in the upper chamber.

The power supply occupies close to half the depth of the case.

Unlike the previous power supply, which was only sold bundled with Antec cases,
this version of the case uses a slightly modified version of one of Antec’s
retail power supplies: An EarthWatts 380. This provides an extra 80W of capacity compared to the 300W unit in the NSK-3300, and makes PSU swap simpler, as ATX power supplies are much more common than SFX ones. That said, most users should have no need to replace the stock power
supply. Our review found
it to be reasonably quiet, very efficient, and well made by a reputable manufacturer
(Seasonic).

A familiar label…

While the label does say EarthWatts, the power supply isn’t quite identical
to the retail version; the cable lengths have been modified to be more appropriate
for such a small case. Several of the cables have been shortened, and the SATA
cables have plugs just six inches from the back of the power supply — just
where they are needed in the top chamber.

There are a total of seven cable sets:

• 13″ cable for main 24-pin ATX connector
• 13″ cable for AUX12V 4-pin
• 18″ cable for 6-pin PCIe connector
• 23″ cable with three 4-pin IDE drive connectors
• 33″ cable with three 4-pin IDE drive connectors and one floppy connector
• 2 x 25″ cables with two SATA drive connectors, one at 6″ and one
  at 25″

The main ATX cable is pre-routed through the side cable port, as it does not
fit through properly without having to remove the power supply. All the remaining
cables are tucked into the top chamber, waiting to be routed as the user desires.

While the larger power supply is more convenient for replacement, it does come
at the cost of space in the upper chamber. Antec states that optical drives longer than
6.9″ are incompatible with the NSK-3480, but even our short 6.5″ drive
was a tight fit.

Part of the problem is the position of the cables as they leave the power supply
along the right side of the case. With the access port between the two chambers
on the left side, this means that the cables must run with full width of the
case in the upper chamber — and then back down again to reach the motherboard
on the other side.

Power supply on the left + Short optical drive on the right = Limited clearance.

The fix is simple enough: Turn the power supply upside down. Antec has conveniently
designed the backplate to allow the power supply to be mounted in either orientation
(owners of 120mm fan PSUs take note!), and flipping the power supply means the cables
leave the power supply on the left side of the case — right next to the
access port. Even better, flipping the power supply gives the short ATX and
AUX cables an extra four inches of slack and keeps the cables out of the intake
airflow. The photo below shows how neatly the cables leave the top chamber in
this configuration.

The upper chamber is much neater with the power supply mounted upside-down.

THERMAL & ACOUSTIC TESTING

Given the similarity between the NSK-3480 and the previously tested NSK-3300,
a full thermal test was unnecessary. We refer you to the
results of our original NSK-3300 test for details. Overall, we were
very pleased with how the NSK-3300 performed both thermally and acoustically.
The NSK-3480 should be identical.

The top chamber, however, has seen more substantial changes. The different
power supply undoubtedly has a different fan, and a different fan speed to power output curve, which may affect
noise levels. Our test therefore focussed on how the top chamber had changed.

To this end, we used our power
supply testing system to duplicate exactly the loads in the original test without rebuilding the system inside. We were concerned only with the thermal and acoustic properties of the PSU under various loads in its chamber. A Zalman 9500 heatsink running at 5V was
hooked up in the main chamber to approximate the noise profile of the original
test. The 21~22 dBA@1m hard drive from the NSK-3300 test was left out as insignificant.

As the power supply fan was the only variable source of noise in the original
test, any audible changes in this test reflects the new EarthWatts power supply.

TEST RESULTS

Ambient conditions were 22°C and 18 dBA. It was 2°C cooler than during the
NSK-3300 test. The ambient noise was unchanged.

At idle, the noise profile was about the same as the older version of the
case. The reason was quite simple: In both cases, the dominant source of noise
was the TriCool 120mm system fan, which mostly produced the whoosh of turbulence noise.
The default noise level was quiet and easy on the ears, but not quite silent.
With only the power supply fan running, much of the turbulence noise disappeared,
and the overall noise level dropped to 22 dBA@1m. Both the system and the power
supply could probably be swapped for slower, quieter models, but most users
will have no need to do this.

Although the noise measurements did rise slightly across the range of tests,
the audible effect was nearly imperceptible. At no time did the PSU fan change in
speed audibly; the increase happened slowly enough that it was inaudible.
Subjectively, there was a sense of a slightly greater volume at full load, but
this was noticeable only under close listening. For practical purposes, the
power supply fan may as well have been running at a constant speed in our test.

This is a significant improvement over the original NSK-3300, in which the power supply
fan started to ramp up at a much lower load, and became easily audible under the highest loads. The NSK-3480 fan will ramp up if you have high enough a load, but there’s no question that it is possible to keep a wider range of systems quiet with
the new power supply. (Exactly how much power the PSU will deliver before its fan starts to speed up significantly will depend on your system details and ambient temperature; we’d guess somewhere around 300W AC input at similar ambient temperature.)

MP3 RECORDINGS

• Antec NSK-3480 — 42~85W 24 dBA@1m: One
  Meter
• Antec NSK-3480 — 135~193W 25 dBA@1m: One
  Meter

• Antec NSK-3300, Config 1 (System Fan @ L) — 24 dBA@1m: One
  Meter, One Foot
• Antec NSK-3300, Config 2 (Rear Fan swapped to Nexus @ 5V) — 23
  dBA@1m: One Meter,
  One Foot

• Lian Li PC-101, Config 1 (No Intake Fan): 24 dBA@1m: One
  Meter, One Foot
• Lian Li PC-101, Config 2 (Intake Fan @ 5V): 26 dBA@1m: One
  Meter, One Foot

CONCLUSIONS

The NSK-3480 is a worthwhile upgrade to an already excellent case.
The new power supply is 80-Plus and has higher capacity, longer cables, and
quieter performance than the original SFX12V unit shipped with the NSK-3300.

The remaining tweaks are minor but welcome for the most part. The relocated
access port between the two chambers ease the cable management concerns that
we had with the original version, and the longer cables should allow things
to be kept neater. The expanded top vent help keep the power supply cooler,
especially in situations where the front of the chamber is blocked by cables
and/or drives. The side vent for the CPU certainly can’t hurt cooling.
If it’s not wanted, or if it seems too much of a noise leak, it’s easy to block off.

The only faults we can find are minor: The short main ATX and AUX12V cables are a bit
awkward to work with, especially with a third of their length taken up running
across the case to the access port. This is quite easily fixed by flipping the
power supply, however. On the other hand, some of the other cables seem excessively
long for such a small case, but the effort required to hide (or simply remove)
the cables is not great.

Overall we came away with much the same feeling we had with the NSK-3300: An
excellent, compact choice for a low-end or mainstream system that doesn’t require
the extra space or heavy cooling of a gaming rig. US$70 for a high quality case
and power supply combo is pretty tough to beat.

Many thanks to Antec
for supplying the NSK-3480
sample.

* * *

Articles of Related Interest
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NSK-3300: Quiet Out-of-the-Box
QMicra from PC Design Lab: SFF Super-sized
Lian-Li PC-101: Aluminum *Can* Be
Quiet
Antec EarthWatts 430: Green Computing Hits
Mainstream
Cases: Basics and Recommendations

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