Excellent review as usual of an excellent psu.
But I'm a little annoyed with seasonic about the 80 plus thing.
These models are nowhere to be found in oem.
In europe, there is a german popular site for buying oem seasonic.
They have the oem s12 (except the 400HT) but since it's not mentionned that it's the 80 plus version, I conclude they don't have that supper efficiency.

Same thing for the ss300fsd.
Worldwide there are several sites selling it including power-on but they say nothing about 80+.
So I suspect it's not the exact psu you tested here.

No doubt, these 80+ exist but it somewhat looks a bit like a marketing thing for seasonic to consolidate their image of "high efficiency psu builder" king.
At least with fortron, there's no trouble finding their high end products.

"it's probably good or cooling" on page 3 is probably supposed to be "it's probably good for cooling".

Ironic --

The 80 Plus program is limited to some of the US states and parts of Canada. It is designed specifically for system builders, not end users. System builders get rebates when they use 80 Plus approved PSUs in systems, and the rebate comes from participating utility companies through the 80 Plus program administered by Ecos Consulting. Please visit www.80plus.org for details. There's little or no incentive for Seasonic to make them available worldwide. I suppose if they get customers requesrting them elsewhere, they will respond...

AFAIK, the non-80 plus versions of these PSUs are also high efficieny, but not guaranteed to be >80% at all loads. Usually it's at the extremes (20% or 100% load) that it might not hit 80%. Otherwise, they are about the same. For example, the S12-500/600 are not 80 Plus approved, but they do have quite high efficiency. The 80 Plus certified versions are OEM, no retail, but have the same model # -- with 80 Plus option.

Any idea where I can buy Seasonic's 80-plus ATX power supplies? They would be a great selling point for the PCs I sell. I looked around at some of the websites mentioned in the article but I couldn't find them (I found Seasonic PSUs, but nothing that mentioned 80-plus).

GHz -- contact www.seasonicusa.com

Thank you, Mike C, for these clarifications.

Since I've finally made my choice of psu after this test, I will no longer bother you with my 80+ concerns

So the noise signature of this ADDA high speed sleeve bearing fan is not as smooth as the medium speed ball bearing fan found in Neo HE?

very nice PSU. i would love to get my hands on one, with one of those "magic bracket"s and fit it in my upcomming SFF case. i would probably mod the bottom of it though, and put in a low speed 120mm nexus fan ducted from the xp-120 on the CPU up to it, and out the back of the case. it said the deminsions of it were 130x125, so a 120mm fan should fit almost perfectly.

No it's not. That Neo HE fan is an exceptional 80mm fan -- I would have to rank it with the Panaflo 80L/M and the Nexus 80 (and a very select few) as one of the best ever. In fact, it is the best stock PSU 80mm fan I've heard.

If we were to look at the 300SFD's Adda fan in isolation, without the S2FC fan controller in the PSU, it would not get high marks from most SPCR folks. BUT, because of the controller, the overall acoustic signature of the PSU is quite good. The controller keeps the fan noise low enough that <150W, it's really not very audible at all.... as you should hear in the MP3 files.

i found a website listing a retail package for this. its in japaneese though. but (hopefully) google has the important stuff highlighted.

they call it a "Super Versatile Plus". the "plus" part add'd on to the super versatile we know designates it as the 80plus version. it has the 80plus logo also associated with it.

Seasonic SS-300SFD

EDIT:

also it seems theirs a 250w 80plus version comming out retail also:

Seasonic SS-250SVP

notice they changed the last 3 letters in the model number from "SFD" to "SVP". i assume the new letters stand for "super versitile plus". so this may also be another way to verify if the model your getting is an 80plus or not.

that image does not mean it's a 80plus certified version. It's just part of the iconographic stuff you found on most recent seasonic psus boxes.

Here's the 80plus logo.

nvm

As far as I can tell, this is the new efficiency king for ultra-low-power setups. 81%+ @ 40W would be great for mini-ITX or undervolted/clocked Athlon XPs.

i called seasonic about purchasing one of these along with the magic bracket that comes with the super versitile. they said they dont sell this product to end users, but told me i could goto Power-on. I told the lady i was their, and saw this model number but that they didnt specify if it was 80plus or not, and asked if all products with this model number were 80plus certified or not, and if not how i can tell if they sell the 80plus version. she said she wasnt sure but took my number and name and said she'd call me back when she found out the answer.

anyone else have any better luck trying to purchase one of these?

MikeC, how exactly did you ask for one that allowed them to send one to you? and did they charge you, or was it free for review purposes?

Seems to me you should contact Power-on to find out whether it's 80 Plus. After all, it's the seller who should know what he's selling. SeasonicUSA sellls to distributors, who then sell to resellers -- it's the way most of these companies work, so it's not a surprise that SeasonicUSA does not know Power-on's invetory.

As for my sample, it got reviewed because Seasonic sent it. I didn't ask for it specifically.

I'm told they are working on another retail package like the older Super Versatile, but with this 300W model. I doubt that these will be 80 Plus certified, but we'll find out.

I happened to be doing a search for a source for the SS-400HT and discovered that CASE-MOD.COM is selling the 80 PLUS versions of both the SS-400HT and the SS-300SFD.

The only source of adapter plates that my searching uncovered is AffordableSurplus.com.

Because of its high efficiency at low power, I'm tempted to try the SS-300SFD in my firewall box that runs 24x7. A DC-DC converter might be even more efficient, but I'd rather not have to deal with another external brick.

I just picked up one of these from Compuvest. It DID come with the magik bracket thing which was nice.

But I was a little disappointed in the noise. The fan was very clicky at the default startup voltage. I was thinking about doing a fan swap anyways, but this confirmed it. Unfortunately, my medium speed Panaflo didn't start at the low 4V level. But to show how cool this thing runs, it didn't start spinning until a least 30 minutes after booting up. By then the air was fairly warm coming out the back. It stopped spinning again shortly after. I didn't really like that. So I dug around and found another panaflo fan. This is an older OEM one from a different power supply that has since been trashed. It's got a yellow label and rated for 0.16A at 12V. Not the most quiet fan but it starts at the low voltage and is much more quiet than the stock fan.

The fan header was extremely difficult to reach. It didn't look like there was any easy way to remove the board from the rest of the case. And the header is way down between the side and a heat sink. It's also not a standard fan header, even for PSUs. So I cut it off from the fan and soldered it to a normal 3-pin header. Now I can put any fan in there I want.

Having succeeded in getting my mid-tower home office pc as quiet as possible, the only noise left to deal with was fan in the Seasonic Super Tornado 300 PSU, which was previously unnoticeable.

I already had a Seasonic SS-300SFD 80 Plus on hand and found that in swapping one for the other, the noise level with the stock fan was slightly louder (by a dB or two) than the Super Tornado's, so there was no real advantage to using it. In addition, when I tried to replace the fan in the SS-300SFD with a Panaflo, I had pretty much the same experience as BillyBuerger (above). Ditto with the 120mm fan in the Super Tornado.

However, one observation that I'd like to pass on is this: Using both PSUs with their stock fans in the same mid-tower case, Everest reported higher CPU and motherboard temperatures (by about 3°-5° C) with the SS-300SFD than with the Super Tornado. It seems that aside from cooling the PSUs, the fans are also an important tool in evacuating hot air from the case, giving the Super Tornado's 120mm fan the edge. Therefore, one may want to consider this choosing the PSU or replacement fan.

In this comparison, the CPU and motherboard are a 1.6Ghz Pentium M in an AOpen i855GMEm-LFS, a combination that tends to run hotter than Intel's spec would suggest. Of course, depending on your choice of hardware, this may or may not be an issue. For example, I also have a 3200+ Athlon 64 (Venice), than easily runs 10° cooler than the Pentium M (31° C vs. 41° C), but consumes more electricity (50-60W average for the Pentium M vs. 65-85W for the Athlon, similarly equipped), so the slight rise in temp with the Athlon 64 would be of little consequence (I prefer to keep CPU temps at 40° C or less).

Update: An alternative scheme to replace the fans in either the Seasonic SS-300SFD or the Super Tornado, is to remove the cover, unplug the stock fan, and install the new fan so that it's wires exit the PSU enclosure with the other wires. Depending on the pin configuration, you can plug the new fan into a motherboard header or one of the Molex connectors from the PSU, itself. It doesn't have to be plugged into the PSU to start.

Configured this way, it was easy to replace the stock Yate Loon D12SM-12 fan on the Super Tornado 300 with a slightly quieter Scythe S-FLEX SFF21D. Of course, you're now bypassing the built-in fan control, so if your PSU (or entire system) tends to run hot, it's strictly at your own risk.

It's completely incredible for me, how efficient this power supply is for low power systems !!

Most (95%) of the time our computer is in idle state. Why don't manufacturers let us use power supplies that are efficient even the range of 40 to 80 watts ?

Is that so complicated ?

It seems that this power supply tend to demonstrate that it's easy, and not pricy !!

Do someone know if it's possible to mod a power supply for better efficiency at low loads ?

The only PSU more efficient at low loads is the PicoPSU coupled with a high efficiency brick.

I am very tempted to try one of these for my old K6-2 450 system which normally only pulls about 35-40W AC using a Seasonic Super Tornado 300...

Most computers are in idle mode a large part of the time. Modern systems use 10-20 watt idle, but their psu's easily draw double that from the wall. Not testing this system for efficiency at lower powers is a missed opportunity...

...which was corrected in later reviews...you are responding to an article written almost 7 years ago.