Recommended Power Supplies

Table of Contents

Our short list of recommended power supplies for quiet or silent computers. Last update: 25 September 2013.

  • Sept 25, 2013 – Added Seasonic Platinum 520W, bequiet!
    DPP 550W, Rosewill SilentNight 500. Minor changes to text.
  • Feb 10, 2012 – Added Seasonic X1050, Kingwin STR-500, LZW-550
    and LZW-1000; too many models retired from lists to list.
  • Feb 19, 2011 – Demoted Nexus Value 430 to recommended
  • Sept 26, 2010 – Added Corsair AX850, Antec TP750
  • Aug 15, 2010 – Added Seasonic X-400 Fanless
  • May 14, 2010 – Added Enermax Modu/Pro87+ 500W
  • Jan 12, 2010 – Added Nexus NX-5000, Enermax Eco80+ 500W
    and Winmate 130W DD-24AX DC-DC Module
  • October 18, 2009 – Added Seasonic X-650.
  • September 8, 2009 – Complete overhaul of ranking system
  • Updated March 14, 2009 – Added Nexus Value 430 and Silverstone
  • Updated Dec 20, 2008 – A slew of changes – Added Seasonic M12D-850W,
    Sparkle Power SPI250EP, TX650W. SilverStone Decathlon DA700, Antec Signature
  • Updated March 16, 2008 – Added Corsair TX650W.
  • Updated March 2, 2008 – Added Seasonic MII-430 & SII-380,
    Enermax Modu82+ 625; retired several now-discontinued models, and shuffled
    rankings as necessary.
  • Updated Aug 16, 2007 – Added Corsair VX450W
  • Updated July 28, 2007 – Added two models to recommended
    lists and retired a few older now-discontinued models

Dec 1, 2006

Until today, these recommended PSU lists were part of the Power Supply Fundamentals article. The lists and the fundamentals article have been separated for practical reasons. The single article was just getting too long and cumbersome. Separating them means it’s a bit easier to update them more frequently. You’re strongly urged to read Power Supply Fundamentals for a fuller understanding of the complexities around power supplies.

PRODUCTS CHANGE, often without notice. The information provided here is accurate at time of posting, but there is no way to guarantee that the samples we review are exactly the same as the ones you buy. There are just too many variables. Manufacturers often change or discontinue products, and change model names without notice. For a bigger sampling, please check the SPCR Forums for comments by owners/users.


The recommended PSUs are divided into three power categories:

  • Up to 380W
  • 381W to 650W
  • Higher than 650W

There are two recommended ranks: Editor’s Choice and SPCR Recommended. In previous iterations of this reference list, power supplies were ranked numerically on two scales of 1-10 for noise and quality. Now, the fine gradations have been put aside in preference for broader groupings. Products ranked as Editor’s Choice are "best in class" for the various parameters we consider most important: Low noise, high efficiency, high build quality, good value, useful features (more or less in that order). As of February 2012, most EC products are 80 Plus Gold or higher efficiency. Those that are Recommended are just that: Recommended for low noise and good performance on the other parameters.

The rationale for the broader groupings is as follows: PSUs that measure within a couple of decibels of each other (especially at below typical ambient levels) at low and mid power loads cannot be authoritatively differentiated in the context of a real PC system. So many other factors come into play: The ambient noise and temperature, the components being powered, typical usage patterns of the operator, etc. A PSU ranked 9 in the old system might have performed identically to one rated 8.5, depending on conditions. In other words, the fine differentiations could only be identified under our lab test conditions, not necessarily in real use by typical users. Hence, those ranking were not always useful.

Now, when a product is an Editor’s Choice, you know that it’s exceptional in most of the parameters that we consider important. Finding one that’s "perfect" or "ideal" should not be critical because you will get similar results with any of them. If it is important to choose a product that’s "ideal" for you, we encourage you to read all the relevant reviews carefully and use your own judgement.

  • The Date indicates when the model was added to the list.
  • Order of listing: The products are ordered by increasing power rating, from top to bottom
  • Items in bright yellow
    are new entries in the particular list.


The ATX case design designates a certain portion of case cooling to the PSU; the ATX design specification assumes a PSU with a fan. Even though most of the fanless models listed here conform physically to ATX PSU standards, this does not mean they are suitable drop-in substitutes for any system. Due to the reduced airflow not only in the PSU but also through the system, thermal management is a serious consideration for successful use of fanless PSUs.

Ironically, the absence of a cooling fan in the PSU may require the addition of another case fan in the system. Fanless PSUs are generally more suitable for systems that run cooler and draw less power. Before opting for a fanless PSU, we urge you to read all the fanless PSU reviews and the associated forum discussions thoroughly. Plan for adequate system cooling and be prepared to experiment and fine-tune the system for thermal safety.

Keep in mind that we strongly weigh the acoustic performance at <200W when assessing the units for noise. This is because systems typically do not draw more than 200W, even at maximum power. Those seeking quiet systems should do everything possible to minimize power draw because low heat makes low noise much easier to achieve. For higher power PSUs, the noise performance >200W is considered as well, but the <200W is still weighted more heavily, because the vast majority of systems run at much less than full load >90% of the time. (Typically, the load is about at idle 90% of the time.)

In actual use, the difference between a fanless PSU and quiet fan cooled PSU is marginal, as the system using a fanless PSU still needs an exhaust fan which may sometimes have to spin slightly higher than the one in a similar system with a fan-cooled PSU. It is only when systems with the quietest fanned PSUs are pushed beyond ramp-up point of their fan controller that they become significantly noisier than systems with fanless PSU. However, the fanless PSU system will be more stressed thermally unless it has airflow from case fans — in which case, their acoustic advantage shrinks again.

REAL TIME PRICING information on the products can be found using the SPCR Shopping Engine (in the left column, or just click the link).

* * *

Up to 380W Comments
PicoPSU (fanless) The picoPSU is tiny —
70 of them fit inside the casing of a normal ATX power supply. Its footprint
is that of a 20-pin ATX connector. It provides regulated +5V, +3.3V and
+5VSB lines. It passes +12V from an external AC/DC power brick, which can
be fanless. There are several models, rated for up to 150W. Perfect for
silent mini PC projects. Main weakness is reliance on power brick for 12V
line regulation (except for more expensive in-car version.) Reviewed.
Does not include AC/DC adapter, $30~$40. Aug 14/06
Winmate 130W
DD-24AX DC-DC Module
Fanless high efficiency DC-DC converter
for use with 18~28V AC-DC adapter, best for advanced PC hobbyists and silencers.
An alternative to the picoPSU. Added Jan 12/10. Review
Seasonic SS-300SFD
80 Plus
Efficient, powerful
small form factor (SFX) PSU with Seasonic’s excellent fan controller, slightly
marred by a mediocre fan. Reviewed.
Jan 3/06
381 to 650W Comments
X-400 Fanless (SS-400FL)
A most impressive 80 Plus Gold efficient
PSU, fanless or fanned. Stellar electrical performance, extremely sturdy
and well-executed build, all-detachable cables delightfully user-friendly,
and tough under extreme heat over long hours of excessive load. Along with
Kingwin STR-500, best fanless PSU, more than just an X-series PSU without
a fan. Silence <500W, with a trace of electronic noise at full power.
The fanless X-460 is similarly recommended. August 13/10
Modu/Pro87+ 500W
Gold 80 Plus efficiency
matches Seasonic X series. The 500W models are the among most efficient
ATX12V PSUs with a sensible power rating, with excellent noise/power curve.
May 2010.
Fanless 80 Plus Platinum model with
maximum 93% efficiency. Excellent electrical performance. Silent below 500W
with trace of electronic noise at full power. Fanless PC enthusiasts can
choose between this one and Seasonic X models. Added Feb 2012.
Silent Night 500 Platinum 80 Plus
Rebadged Kingwin STR-500. Added May
LZW-550 Platinum
80 Plus Platinum model with maximum
93% efficiency. Silent below 500W with no fan movement, super quiet even
at full load. The enitre line seems worthy. Added Feb 2012.
Dark Power Pro 10 550W
Stylish, feature-rich models made
by Fortron-Source Power rank high for low noise, excellent multi-fan controller
(for case fans), and efficiency.
Platinum Fanless 520W PSU
The very best electrical
performance tested, the highest efficiency. Some questions about electronic
noise (buzz, whine) on early samples is the only cause for hesitation. Otherwise,
this fanless is tops.
First 80 Plus Gold
PSU on market with superb performance, totally modular cabling with patented
DC/DC converter + output connector PCB offers fanless operation at lower
loads and extremely quiet fan-cooled operation at mid-to-high power levels,
with >90% efficiency at mid-power levels. Entire X-series is worthy.
Oct 18/09.
Over 650W Comments
Extension of great 80 Plus Gold X-series
design into KW model. >90% efficiency. Excellent build quality, completely
modular cabling. Silent below 500W, as fan does not spin; very quiet to
~700W. First ever incidence of a PSU with NO electronic noise. 1250W model
also available. Added Feb 2012.
LZW-1000 Platinum
80 Plus Platinum model with maximum
94% efficiency. Silent below 500W with no fan movement, super quiet at 700W
and just 25 dBA even at 1000W! Excellent electrical performance. Like Seasonic
X1050, NO electronic noise, though the physical presentation is a step down.
Easy to believe that the other models in the LZW series share the same properties
as the 550 and the 1000. Added Feb 2012.
80 Plus Gold model made by Seasonic
based on the X-series. Same great electrical performance. Only difference
from X-series seems to be straight voltage control fan instead of PWM. Totally
modular cabling with patented DC/DC converter + output connector PCB offers
fanless operation at lower loads and extremely quiet fan-cooled operation
at mid-to-high power levels. Dramatically increased quiet power range in
thermally advanced case. The rest of the AX range seem to share the same
basic characteristics, and Seasonic X-series lineage. Sept 26/2010.
An innovative PSU
with 120mm in-line fan only compatible with four large Antec cases, the
CP-850 is just about as quiet as the Nexus Value 430 at lower power, stays
extremely quiet and cool in those cases to >600W, with exactingly clean,
regulated voltages lines at a price that’s a pittance for such quiet, abundant,
performance. Relatively modest 85% efficiency (in 2012) for an Editor’s
Choice. CP-1000 not tested but offers similar performance. Sept 08/09

* * *

Caution: Not Brothers Under Their Skin

When it comes to the noise they make, PSUs of the same brand, even of the same series, are not that closely related sometimes. While some PSU brands are pretty consistently quiet (Seasonic is a good example), individual models still vary. Some brands are less consistent. This is especially true of brands whose power supplies are made for them by OEMs, often more than one at the same time, for the same or similar series. Which brands have their PSUs made by other companies? Why almost all of them — all but three names on our recommended lists: Seasonic and Fortron-Source / Sparkle (closely related), who actually manufacture their own products. Enermax used to, but some of their products are now subcontracted out; we don’t know what percentage or to who.

So be warned. Don’t assume that since Super Quiet 500 received an Editor’s Choice award, the same brand’s Ultra Silent 1000 must be very quiet too. If we have not reviewed it, if it’s not on these lists, it’s best not to assume. At least inquire in the forums. SPCR does not make assessments of products without examining them, and we generally choose not to review products that don’t meet our minimum requirements for "quiet". The reviews take a great deal of time and effort, and we prefer to save it for better products. So… sometimes "holes" in our recommendations of products in a series may exist because those models simply did not make the grade.

* * *

Up to 380W Comments
Seasonic SS-200SFD Very quiet 200W with sleeve-bearing
fan in smaller case (SFX form factor) for Flex-ATX case, smart S2FC fan
control for minimum noise. P4 12V connector. Good for custom small form
factor systems (used in Breadbox
) and as replacement for eMachine, HP, and other OEM PCs. 9/02.
Sparkle Power SPI250EP 80 Plus means 80% efficiency even
at a low 50W load. Decently quiet in stock form, it’s a perfect 250W OEM
model for modders to silence even further for a low power, high efficiency
eco-box. Reviewed.
May be hard to find at any price. Dec19/08.
Seasonic S12II-380 The second generation S12 seems mostly
to be a refresh of the first, with only a few significant changes, including
incrementally higher efficiency. Seasonic’s trademark fan control system
reamins just about the best in the business: Very quiet from idle to some
300W or higher, yet with good cooling when needed. Reviewed.
March 2008.
381 to 650W Comments
Silentmaxx Fanless 400W MX460-PFL01 A higher power version of the Fortron
Zen, sold under a different label. It exhibited similar characteristics
and higher output. Like the original, pretty solid and silent, but with a trqace of electronic noise at higher loads. Reviewed.
Aug 14/06
Nexus Value
Innocuous little
ATX12V power supply from silent component pioneer Nexus is a
quiet champ, offers unexceptional but yeoman-like performance. Efficiency isn’t the best, and we’ve had a few reports of standby issues. Reviewed. Mar
Enermax Modu82+
Modular cabling, high efficiency, excellent electrical
performance, and acoustics that are incrementally quieter than most of the
best. Pro 82+ offers same performance w/o detachable cables. Reviewed.
March 2/08. Caution: Some users report early fan noise
problems. Demoted from Editor’s Choice due to plethora of higher efficiency competition with similar acoustics in Feb 2012.
Nexus NX-5000 >85% efficiency,
excellent electrical performance, compact size, and acoustics that rank
with the best. Review
Added Jan 12/10.
Seasonic M12II-430 2nd gen of Seasonic modular cable
PSUs consists of only two models at the moment, the 430 and 500. They’ve
lost the secondary 60mm fan, which is a plus, but may still have higher
than usual turbulence noise at high load (compared to other Seasonics) due
to a plastic fan baffle. Still excellent noise and electronic performance.
March 2008.
Antec Signature
(and 850)
Innovative new
two-board design for improved cooling with an 80mm in-line fan, superb build
and component quality, Antec’s first collaboration with Delta Electronics
is one of the most interested PSU to come along in years. It’s also highly
efficient and very quiet. Reviewed.
Dec 20/08. Note: The 850 was not reviewed, but we know
from hands-on experience that it has the same qualities as the 650. Demoted from Editor’s Choice due to plethora of higher efficiency competition with similar acoustics in Feb 2012.
Over 650W Comments
TruePower New TP750
Virtually silent to ~250W load, pretty
quiet to near 400W, and better in a thermally advanced case. It’s another
one made by Seasonic. Modular design with good 86% maximum efficiency, with
very good electrical performance and modest pricing. For those with lower
power needs, 650W and 550W models have the same heatsinks, so should have
the same noise/power curve. Sept 26/2010
SilverStone Decathlon DA700 It’s quite quiet to about 300W load,
beyond which the fan ramps up to high speed quickly. A modular design with
good efficiency, our sample may have had a subtly damaged fan. Dec 20/08.
Coolermaster Silent Pro M700W High efficiency, good build quility,
low noise at lower power, marred by too linear a fan controller. Still,
it can be easily integrated into a quiet system, getting louder only when
pushed to gaming power levels. Sept 09.
Nexus RX-8500 Another one with a 135mm that very
quiet at low and mid loads even if a bit fast to ramp up as power load increaes.
Still very quiet at full and near full load. Sept 09.

Please go to the next page for the Retired Recommended PSUs.

* *

Articles of Related Interest
Power Supply Fundamentals

Power Distribution within Six PCs
Desktop CPU Power Survey,
April 2006


Discuss this article in the forums


There are many reasons for these PSU models to be retired from the Recommended PSU List. The most common reasons are:

No longer available. If they are more than ~18 months old, chances are the manufacturer has revised, updated or replaced them.

Does not support latest ATX12V spec. Intel has made many changes in PSU design guidelines in the last two years, and the latest motherboards and components require a PSU that provides most of its power at 12V.

Too long since review. Even if a product is still available relatively unchanged, which is very unlikely, if we have not examined it for a couple of years, it’s an automatic retirement.

The retired models may still be available in some markets, and they may still be quite suitable for many systems. If you have one that’s working quietly for you in your system, be happy.

New entries are in darker yellow rows.

RETIRED Comments
Antec EarthWatts 430 It’s basically an 80 Plus certified, non-detachable
cable version of the NeoHE with a slightly louder fan. Still pretty quiet,
even to a fairly high power load. Reviewed. DISCONTINUED. Retired from active list Feb 2012.
Antec Truepower Trio 550 120mm fan model, Good overall performance, quiet
up to ~200W load. Surprisingly inexpensive. Reviewed.
July 28, 2007 DISCONTINUED. Retired from active list Feb 2012.
TruePower 380
Quiet, 380W unit; 2 fans noisier than quietest 1 fan models. Unique outputs for case fans to keep them at same low voltage as PSU fans. Independent voltage lines. All TruePower models should exhibit the same noise level. Early samples exhibited unexplained coil buzz on reference P4 system; not heard in later samples. First-hand. Price: $70. TOO LONG SINCE LAST EXAMINED. retired April 2005.
Phantom 350
>80% efficiency, strong dual-12V current capability of 34A combined, and seemingly effective cooling for all internal components by conduction to the heavy external casing. Slight buzzing inaudible in normal use, 3 year warranty. No PFC in 120VAC model; APFC in 230VAC EU model. Reviewed. Price: ~$150. Caution: First production run seems to have a high rate of failure, which Antec has dealt with responsibly. Q rating marked down 1 point until reliability looks improved. See this SPCR Forum thread. PHASED OUT. Dec 1/06.
Antec SmartPower 2-450
Dual 80mm push-pull cooling, with external fan that turns only at higher loads. Very quiet at low load, gets noisier more quickly with load than higher ranked models on this list. Good performance, good cooling, good efficiency. Reviewed. DISCONTINUED. July 28/07
Antec NeoHE 430 Middle model in series offering ~80%
efficiency, detachable output cables, multiple 12V lines, APFC, auto-range
AC input, quiet fan and intelligent fan controller. The 80mm fan is a very
quiet ball-bearing Adda. Other models likely have similar acoustics and
performance. Only a touch louder than the Seasonic S12-330, 380 & 430 models
in actual use. Reviewed.
High incompatibility issues appear to have been largely solved in
the first quarter of 2006. DISCONTINUED. Retired from active list Feb 2012.
TrueControl 550
Quiet at under 100W power delivery, modest up to >150W, incredibly full featured with manual fan speed bypass, fine line voltage adjust on front panel (of PC!), outputs for case fans to keep them at same low voltage as PSU fans, and a spare 4-pin DC output on back panel, this 2-fan model puts out very tightly regulated voltage on all lines all way to its max power of 550W. Same guts as TruePower and TrueEPS12V models. Reviewed Price: ~$160 TOO LONG SINCE REVIEW. retired April 2005.
Be Quiet! Dark Power Pro 430 Good quality, fairly high efficiency, low noise power supply only for 220VAC, competitive pricing. Availability limited to the EU. Reviewed. Oct 12/06. DISCONTINUED. retired from active list Sept 2009.
Chill Innovation CP-700M Very quiet up 135mm fan up to ~500W,
not quite the highest efficiency, available primarily in the EU. Worthwhile
alternative for quiet-seeking gamer. Reviewed.
Sept 09. DISCONTINUED. Retired from active list Feb 2012.
CoolMax Taurus CF-300 The black anodized aluminum casing acts as a big heatsink and efficiency is very high. It not equipped with PFC at all. 12V current is 15A, a bit low by today’s standards, it seems to run fairly hot, and the sample unit showed a malfunction in not turning off normally although otherwise OK. Recommended with caution. Reviewed. Price: ~$150. MANY BETTER MODELS NOW AVAILABLE retired Oct 2005.
Corsair VX450W 80 Plus level efficiency, even down
to pretty low output load, very quiet to a very high output level (300W
on our test bench), made by Seasonic, very well priced, hard to fault. Reviewed.
Aug 16/07. DISCONTINUED. Retired from active list Feb 2012.
Corsair HX520/620 Combines the modular cabling of the
Seasonic M12 with the quieter single 120mm fan cooling configuration of
the S12. Highly efficient. About the best balanced of Seasonic’s current
offerings (under its own brand or other brands.) Reviewed.
Nov 17/06. DISCONTINUED. Retired from active list Feb 2012.
Corsair TX650W 80 Plus efficiency, very quiet to
a high output level (300W on our test bench), made by Seasonic, well priced,
hard to fault. It’s basically a higher power version of the VX450W. Reviewed.
March 16/08. TOO LONG SINCE REVIEW; CURRENT PRODUCTION MAY BE CHANGED. Retired from active list Feb 2012.
Enermax Eco80+
Good all around
performance and very low noise that just misses Editor’s Choice class performance;
the fan ramps up at a slightly lower load than most EC power supplies. Review
Added Jan 12/10 DISCONTINUED. Retired from active list Feb 2012.
Enermax NoiseTaker 475 High efficiency for this 470W non-PFC model. Though min. noise is bettered by other models (in med & high power categories) due to dual fans’ bearing noise, for high power systems, it will stay at min spin speed to much higher power level and temp. Cables way too stiff — but improved in later production) Reviewed Price: ~$99. April 4/04. DISCONTINUED; replaced by 495AX. Jan 3/06

Enermax Noisetaker 701

A 600W model with high efficiency optimized for the new generation of very high power dual-VGA SLI systems. Not as quiet as the 475, but quiet considering power capability. Cables now much more flexible. Reviewed ~$170. April 5, 2005. NOTE: This unit has been replaced by an SLI-certified 701AX with PCIe connectors; it’s not identical to the sample tested, but acoustics are said to be the same. DISCONTINUED. July 28/07
Enermax Noisetaker 325 Identical technology as Enermax Noisetaker 475 below, but with Active PFC: Very high efficiency, very low noise, smart fan controller. Based on Firsthand experience. June 2004. DISCONTINUED. Jan 3/06
FSP Green PS FSP400-60GLN Environmentally friendly power supply
manufactured from recyclable and nontoxic materials offer high efficiency,
stable power, good cooling and low noise with lower component density, all
at a decent price. Availability seems spotty. Reviewed
Price: ~$70. Jan 03/6. SURPASSED BY MANY OTHERS. Retired from active list Feb 2012.
Fortron FSP350-60PN Aurora 120mm blue-LED fan, manual speed control, small heatsinks, linear thermal fan control. Default noise level is higher than with most 80mm fan quiet PSUs, humming more than most. High cooling power when fan speeds up. Reviewed Price: $75. 6/02. TOO LONG SINCE REVIEW. retired April 2005.
Fortron Zen FSP300-60GNF The highest efficiency of any fanless model (>84%) and second only to Seasonic’s SS400HT “80 Plus” model, modest dual-12V current capability of 22A combined. Uses large internal heasinks and wide open mesh cover for convection cooling, which may be a bit suspect. Lower than usual price for fanless design. APFC, auto-range AC input. Reviewed. Price: <$100. Sept 2005 SEEMS DISCONTINUED. Retired from active list Sept 2009.
Nexus NX-3000
Very quiet, with tight line voltage regulation and good cooling despite quiet fan. Looks similar to Zalman. Passive PFC. Stamped grill vent only downside. Reviewed Price: $75. 11/29/02. TOO LONG SINCE REVIEW. retired April 2005.
Nexus NX-4090
120mm fan PSU based on Fortron design, with good performance and good cooling is very quiet to ~150W load. In actual use, slightly quieter than earlier NX-3500 model. Fan ramps up too quickly. For low noise operation, care must be taken to ensure good case airflow. Reviewed June 17/03. Price: ~$100. April 5/05. Old outmoded design, long surpassed. Aug 14/06
Nexus NX-8060
120mm fan 600W PSU with modular cabling from one of silent
computing’s oldest names. Good performance, cooling, and efficiency, but
flawed by linear controller that speeds up the fan a bit too soon. It’s
quiet at lower loads, but needs a separate thermal chamber to stay quiet
at higher loads. Reviewed.
July 28, 200. Also see NX-8060
PSU improved
DISCONTINUED. Retired from active list Feb 2012.
Nexus NX3500 120mm fan 350W PSU w/smooth sounding fan that’s very quiet at default level. Fan ramps up too quickly. Overall performance similar to 120mm Fortron. Reviewed Price: $80. TOO LONG SINCE REVIEW. retired Sept 2005.
Nexus NX-4000
Quiet high power PSU based on Fortron design, with tight voltage regulation, high over-current capability and very good cooling. Simple linear themperature / voltage curve in fan control circuit seems same as in SilenX 400; this plus ball bearing noise in fan inhibits noise performance. For low noise operation, care must be taken to ensure good case airflow. Active PFC. Rugged looking construction. Reviewed Price: ~$105. TOO LONG SINCE REVIEW. retired April 2005.

Q-Technology QT-02300

Quiet thermister controlled fan remains that way under substantial load. Excellent quality fan, low airflow, runs hot, and case airflow suffers somewhat. Good sized heatsinks. Q marked down for some coil whine in test system. Needs good case airflow. Active PFC. Reviewed Price: $79. TOO LONG SINCE REVIEW. retired April 2005.
M12D 850W
The first superpower
model from Seasonic is a 80 Plus Silver model, highly efficient,
modular, and equipped with a new top quality Sanyo Denki fan. With the Enermax
Modu82+, it’s become the one to beat. Dec 20/08. HARD TO FIND, PROBABLY DISCONTINUED. Retired from active list Feb 2012.
Seasonic S12 Energy+ 550/650 Most efficient of Seasonic’s current lineup, 80 Plus certified. The fan controller appears to be tweaked for lower noise even to very high power loads. Very quiet! Efficiency at very low loads (<65W) is no better than other models of similar rating. Reviewed. Oct 5/06. DISCONTINUED. Retired from active list Sept 2009.
Seasonic S12-430 Higher efficiency and very low noise (18~22 dBA@1m) up beyond fairly high power loads (~200W). ATX12V 2.0 compliance, high 12V current capability, excellent fan controller and quiet 12cm fan. Reviewed. Price: ~$100. April 5/05. REPLACED BY S12II SERIES. retired March 2008.
Seasonic S12-500 / 600 These 500W and 600W models have different circuitry than the lower powered S12s, slightly higher noise, and even higher efficiency. ATX12V 2.0 compliance, high 12V current capability, PCIe VGA connectors. Excellent fan controller. Reviewed. April 5/05. REPLACED BY S12II SERIES. retired March 2008.
Seasonic M12-600/700 Seasonic’s first modular cable PSU line, the M12 also sports a secondary 60mm fan meant to address the problem of a hot spot which probably afflicts all 120mm fan designs. Very quiet at lower loads, even up to mid-200W, but once the 60mm fan starts, it never shuts off, which makes it a bit noisier than other Seasonics. The high power ratings make it clear it’s aimed at gamers and performance nuts. Reviewed. Oct 11/06.
Seasonic S12-330 & 380 The 330 is similar to S12-430 but the fan tends to get faster at slightly lower power than high power models. Newer sleeved version reviewed. The 380 was not officially tested but is used around the lab. It has the same size heatsinks as the 430, so the noise curve is pretty much identical to the 430. Aug 14/06. REPLACED BY S12II SERIES. retired March 2008.
Seasonic SS-400HT 80+ Same circuitry as in S12-500/600, this is a specially modified 80+ approved model that has higher efficiency especially at low loads. Same characteristics as the S12-500/600, otherwise. >85% max. efficiency is highest measured with newly calibrated test rig (v3). Probably very hard to find, as it is a non-retail product. Reviewed. Sept 2005. No longer available, retired March 2008.
Seasonic Super Silencer 300, 350 Identical technology as Seasonic Super Silencer 400. Very high efficiency, very low noise, smart fan controller works very well in Rev. A3 released ~end of May ’04. Based on Firsthand experience. BEING PHASED OUT. retired April 2005.
Seasonic Super Tornado 300 With Super Silencer series, among the highest efficiency PSUs available, up to 78%, and >75% efficiency at any power level. 120mm fan. Active PFC, cable management kit, ATX12V v1.3 compliance, very high 12V current capacity. 3 yr warranty. When in a good airflow case, review samples are the quietest tested thus far and would be at the top of this list; however, a portion of the first batch have had significant fan noise & non-start issues, and buyers are cautioned to read through the PSU forms. Reviewed. Rev. A3 released late May ’04 corrects previous fan controller inconstencies and improves efficiency to over 80%. Rev.A3 review. Price: $65. REPLACED BY S12 SERIES. retired April 2005.
Seasonic SS-300FS Active-PFC Quiet 300W, neck & neck with Zalman. High efficiency. A bit of fan ball bearing noise keeps unit from the top of this list. All Seasonic PSU utilize their smart S2FC fan control for minimum noise. Active PFC for excellent energy conservation. Note: All Seasonic PSUs feature the S2FC fan control 6/02. Reviewed Price: $59. Comments revised June 9/03. PHASED OUT. retired April 2005.
Seasonic SS-300FS non-PFC Modestly priced Seasonic has 2 main differences from APFC model below – no PFC and a sleeve-bearing fan that is at least 2 dBA quieter and much smoother sounding. High >75% average efficiency. Reviewed Price: $45. June 19/03. PHASED OUT. retired April 2005.
Seasonic SS-400FS APFC Higher power version of SS300-APFC with S2FC fan control is quietest 400W unit encountered. Noise performance is actually better than 300W-APFC model because fan speed is kept low to a higher temperature/load. Active PFC. Firsthand. Price: ~$99. Comments revised June 19/03. PHASED OUT. retired April 2005.
Seasonic SS-200SFD Very quiet 200W with sleeve-bearing fan in smaller case (SFX form factor) for Flex-ATX case, smart S2FC fan control for minimum noise. P4 12V connector. Good for custom small form factor systems (used in Breadbox PC) and as replacement for eMachine, HP, and other OEM PCs. 9/02. Price: ~$32 SEEMS DISCONTINUED. Retired from active list Sept 2009.
Shuttle SilentX 250 Quieter 250W PSU in long & narrow form factor replacement model for most Shuttle SFF systems. Uses two 40mm fans in push/pull config; they do ramp up under load. MSRP of $70 seems steep. Feb / 05 SEEMS DISCONTINUED. Retired from active list Sept 2009.
SilenX 14dB 400W Good quality Fortron-based model with massive HS and quietest 80mm fan ever encountered. Starts inaudibly but ramps up to much higher volume under load due to simple linear themperature / voltage curve in fan control circuit. Airflow is very low, so great care must be taken to ensure very good case airflow to ensure quiet performance. Reviewed Comments revised June 19/03. Price: ~$119. TOO LONG SINCE REVIEW. retired April 2005.
Nightjar ST45NF
Higher power version
of ST30NF, with 80 Plus Bronze efficiency. Very good build quality, excellent
performance all around. Pricey (typically
) Reviewed.
Mar 14/09 DISCONTINUED. Retired from active list Feb 2012.
Silverstone ST30NF Heatpipes transfer the heat from internal heatsinks
to the heavy external casing, which is essentially a 6-sized heatsink. Near
80% efficiency comparable to Seasonic Super and Enermax Noistake series,
along with Active PFC. 12V current capability is adequate at 17~18A. LEDs
indicate thermal condition. It also looks sleek and high tech in natural
aluminum extrusion casing. Reviewed.
Oct 18/04. DISCONTINUED. Retired from active list Feb 2012.
Silverstone Element ST50EF-Plus 80 Plus certification and high efficiency
competitive with the best, along with good acoustics to >250W load, and
a nice fan controller, with a tendency to coil whine at very low loads (not
unusual). Reviewed.
Nov 17/06. TOO LONG SINCE REVIEW. Retired from active list Feb 2012.
TKPower 300 Fanless PSU only suitable for lower power systems. Runs hot. Not recommended for P4 systems. Non-standard form factor requires custom fitting into case. Maximum recommended load without fan is ~80W. Requires fan for full 300W power output. Q marked down because of preliminary coil noise in sample that mysteriously faded to very low levels after some weeks. Article 7/02. Price: ~$195. BETTER OPTIONS NOW. retired April 2005.

PC Power & Cooling Silencer 275ATX

Quiet performance by single fan 275W unit from one of the earliest quiet PSU makers. A little bearing chatter may be specific to test sample, as samples of 80mm fan used in unit don’t exhibit same. Decent HS, build quality. Combined 3.3V + 5.5V rating lower than 300W units. First-hand. Price: $79. TOO LONG SINCE REVIEW. retired April 2005.
Verax F300PPFC-80KP
As quiet or quieter than Nexus NX3000, with identical characteristics except the fan. Unusual “static” noise signature to Verax fan, which has very little low-frequency noise. Reviewed Price: $EUD119. 11/29/02. TOO LONG SINCE REVIEW. retired April 2005.
Zalman ZM300A-APF Quiet 300W, cool operation, big heatsinks, intelligent fan control. Handy 5V/12V multiconnector for fans. Active PFC. Sample exhibited a negligible amount of coil buzzing. Reviewed Price: $75. 6/02. TOO LONG SINCE REVIEW. retired April 2005.

Zalman ZM460-APS

Based on the Fortron Green but with
a better quality fan, this is the quietest PSU from Zalman yet. Pretty high
efficiency, good cooling, and low noise to >200W load on our test bench
make it a reasonable alternative to other top quiet recommendations. Reviewed
April 5, 2005. DISCONTINUED. Retired from active list Feb 2012.
Zalman ZM400B Similar to Nexus and SilenX 400W models, this rugged PSU is based on the ATX12X V1.3 compliant Fortron, with higher 75% efficiency. Noise is similar to 80mm Nexus PSU. Nice package and handy multiconnector for fans. Reviewed ~$110. Old outmoded design, long surpassed. Aug 14/06
Zalman ZM1000-HP It’s a 1000W PSU, and it’s quiet
enough to take on all comers. It starts at ~20 dBA@1m and stays under 30
dBA till around 600W load. We never thought we’d say it, but it’s a kilowatter
that even silencers would like. Electrical performance is not tops, however,
and efficiency could be better. Reviewed.
Dec 20/08. TREPLACED BY NEW MODEL. Retired from active list Feb 2012.

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