Great article, I agree on the price being too high.

M12 and S12E+ apparently use improved version of S12's design so that would explain lower consumption.

I would keep it worth of mentioning that in reality there aren't any virtual 12V rails with current limiting meaning there won't be problems in distribution of load.


And high quality and cheap price meet rarely if even then, quality component's like Japanese capacitors cost more than some generic "made somewhere in Asia" capacitors. (Seasonic made Antec Neo HE uses cheaper components, starting from single side PCB made of cheaper material)

Going through hot box test with flying colours at these temperatures tells something about quality...
http://www.jonnyguru.com/review_deta...=13&page_num=2

got me the 700W version a couple of months ago, very nice PSU, very quiet compared to the crappy levicom 550Watt I had (never going cheap again on psu :s first Q-tec then this one..) + higher and more stable 12V lines 5V lines, 3V lines.

bought the 700watt for my amd xp 1700+ which gets about 1.76-1.79Vcore + radeon X800XT@ XT PE

the reason I got the highest Wattage PSU (i know its high for my setup ) is that I figured the higher wattage model will be more quiet than a lower wattage psu + future upgrade to conroe + dx10 cards.

You don't need to change PSU at least for next 10 years unless used voltages and connectors are changed.
And unless you're going for 8800GTX SLI with quad core CPU you can run also other PC from it without it even sweating.


Wattage doesn't have really much anything to do with how quiet or noisy PSU is at certain load. Biggest factors in that are efficiency and design of cooling.
Amount of produced heat (high efficiency PSU can produce just half of heat produced by PSU with efficiency normal couple years ago) and heatsink design affects to what amount of cooling capacity is needed, which again affects to required airflow.
Fan size again affects greatly to required RPMs for achieving needed airflow, smaller fans need higher RPMs which means more and higher pitched more annoying noise.
Also noise level of similar sized fans varies according to quality, differences in that can be quite huge.


In fact high power PSUs have lower efficiency at light loads like sub 100W compared to "medium" power PSUs if quality of design is similar.

Also 12cm fan of 700W model is high speed version vs. medium speed version in lower models, fan control circuitry just keeps its RPM similar to medium speed fan of lower models until that extra airflow is needed at highest output.

700w for that setup was pointless, a decent 300w would pull it. And you wouldn't need the 700w for a conroe + dx10 either, only if you're going berserk on the overclocking, loads of ram and sli.

Another thing that should be added to the review however, is that the 60mm fan does not start up at boot, only starts up if a threshold is reached, but then never stops again.. Even if heat/power/voltage goes back to normal levels.

expensive yes but if you look at the insane efficency, the noise levels and the stability of the voltages for a modular PSU, it is exceptional


the 700W range is only needed for GTX SLI and the 1 KW products are only needed for AMDs Quad FX with SLI

Seasonic M12 having problem starting ; or any high efficiency PSU having the same issue-
http://www.2cpu.com/forums/showthread.php?t=79771

I have had two M12 600; both could start with a single 80mm fan.

direct link : http://www.silentpcreview.com/article28-page5.html

Higher efficiency PSUs generally tend to need higher minimum power on the 12V line in order to simply run. Typically, we're talking about 1A or greater. Older, less efficient PSUs have much lower minumum current needs, under 0.5A and often ZERO.

In some recent motherboards, there are various time delays implemented in order to ensure that the PSU (and motherboard) is not subject to a huge current surge when everything turns on all at once. Many Asus boards have been identified as doing this, al though you won't get Asus to talk about it — I tried — they will say it's proprietary information they don't want to share with competitors. They are not the only board makers doing this.

good info there

What I mean to say is, how does one determine if this going to be a problem for them. As I would prefer using an ASUS board (P5N32-E SLI). Using the xtreme PSU calculator it tells my Peak wattage would be at 684 watts. Anyways I was considering M12 700 watt Seasonic or 620 Watt Corzair. I would really like to be above my peak wattage (assuming xtreme PSU Calculator calculates for peak wattage). Most people tell me my system wont need more than 500 watts. So im not even sure what kind of power supply im gonna need. And I would really hate run into this problem. Either that or not be above Peak wattage.

Using the same calculator the test system was at 432 watts using 80% utlization and 0 surge factor; with 50% surage factor it was 682 watts.

Silentpcreview found both S12E+ and M12 models capable to starting without any load.
And 700W M12 I have here starts without load. (with that clicking sound mentioned in S12E+ review)

That calculates BS... PR wattage applicable to non-quality PSUs, not peak wattage.


PS. For comparison around price 850W Enermax Galaxy which costs arm and leg surely loses for 600W M12 in game PC use because of its completely idiotic (and that's too mild word!) 12V rail distribution which doesn't leave even 400W available for graphic cards!

The two review samples started without load here.

calculates PR? whats PR... not familiar with that lingo. so extreme PSU doesnt calcualte maximum wattage used? What is it calculating then? In any case, What is the purpose of those links posted earlier back then... the ones about the PSU not able to draw enuf minimal power to boot up the PC? and the delay timings to prevent surges? What I mean to say is... if you guys are saying I can go with seasonic M12 without problems for booting up, what is the significance to those past links? ( i dont mean to sound patronizing, or condescending) I just honestly want to understand what this means... thats all. So if Extreme PSU Calc came up with 684 watts what does that number mean? and which model PSU should I go with out of these 3 seasonic M12 600, seasonic M12 700, or Corzair 620? Im sorry, Im just really confused, and when I buy all my parts for my pc i just really want to be able to get up and running as soon as the parts get mailed I appreciate your response in light of my "noobness"

Marketing aka BushSh*t wattage, applicable to low quality PSUs whose ratings are exaggerated by BS departments.
In SilentPCreview forums there's people running PC with under 400W Seasonics when that calculator gives ~500W power requirements.

CPU and graphic card are only major power consumers so calculating consumption manually from TDP values/measured real consumption gives much more accurate results. (in normal PC rest of the parts would consume something like 50W)
So could you list components? (no need to list fans, and HD/optical drives only when there's more than one)


I would classify that as one of those "Heavenly bodies in wrong position"-problems... maybe those were from very early production lot.
Even the most known start problem PSUs, Antec Neo HEs (Seasonic made) have artificial load system for no load starting capability in later versions.


Corsairs, Seasonic S12E+ and M12s are all based to same one 12V rail design.
S12E+ serie (550W and 650W models) is similar to original S12 serie, fixed cables (lot of) and 12cm fan. M12s have modular cables and secondary low speed 60mm fan for spot cooling front end's hot spot which more or less exists in all 12cm fan PSUs. Corsairs are little like between, modular cables (but flat cable type so don't bend in all directions) and 12cm fan.

Noise level of M12 is very slightly higher than that of others after 60mm fan starts (somewhere between 250-300W load but depends on temperature of PSU/cooling air) but at loads were difference would be bigger I don't think it would be noticeable over cooling noise of PC's components, also it should definitely help in cooling of PSU in case of less than good case cooling.
Components should be same in all so I'm not sure what explains considerably cheaper price of Corsairs... lesser testing in factory could be one reason. (propably one of the most time consuming=expensive phases in production)

At least if you're considering it possible that you have at some point top end dual graphic card PC in that case 700W M12 has one definite advantage, 4 PCIe power connectors. (8800GTX requires two connectors, like R600 based Atis propably do also)

I beleive you have already posted a response in another forum thread of mine at JonnyGuru's. But, I can give you the link. Here you will find my list of components as well. Although, all of you have made a considerable contribution of knowledge to me. I believe im starting to FINALLY grasp this powersupply issue with myself. You all have been SO helpful. I cant begin to thank you enuf. I cant stand it when I dont understand the inner workings of things. And this just makes me feel more confident in my Rig when I do. So again, I wouldnt of gotten this far without your help.


-Thanks so Much, this has definately been a pleasurable and FUN learning experience.