i just ordered a Nexus NX-3000 from siliconacoustics and after reading the review and updates i think im gonna return the Nexus NX-3000 for a full refund and purchase a Seasonic Super Tornado. I guess i should call them to see if they carry Rev. A3.

I got one from Silicon Acoustics. Their website states that they have Rev. A3, and that's what I got. Their site price is $64.95, but they will price match if you call them (they never replied to my e-mails). Try Froogle for a better price.

Another update:Added three fanless PSUs: Antec Phantom, Silverstone ST30NF and CoolMax Taurus CF-300. A few minor changes to text on page 2.

Mike, I dunno if you saw this in the Antec Phantom thread, but IMO the Seasonic Super Tornado 300 A3 is a step backwards in silence from the A1, since it has a lot more vent holes in the back of the PSU. With the bottom mounted fan, it pumps a lot more heat back into the case, so the case runs hotter, and the hotter case air makes the PSU fan ramp up considerably faster. I modded my vent pattern back to the same pattern as the A1 which makes the case run cooler and the PSU run quieter.

I think Seasonic should revisit the design of this one so the air only goes through the PSU once. Anyway, with a duct tape mod my A3 runs as quiet as my rev A1, but it is not quieter.

I also have a Fortron FSP300-60PN; good for the price, but not the best, and some Herolchoi (HEC) 300W in my server that came with a Compucase; that's a surprisingly quiet supply though it can't make my server quiet...

Is it possible you are a bit confused about how the Seasonic ST 300 works? The 120mm fan pulls air FROM the case and that air cools the PS and it exits out the back. It doesn't "pump a lot more heat back into the case."

well i dunno how you managed to misunderstand that one, mg1394, he's talking about the 'back' of the PSU where the DC cables come out. more vents..

got it. I guess I refer to back and front opposite from you. I'll change.

If the Super Tornado 400 was on the recommended 400W+ PSU list, would it edge out the Super Silencer 400 for the #1 spot? I'm thinking probably so, based on the ranking in the <400W PSU list, but I'm not sure if that extrapolates to the >400W PSU list.

You're right -- the Yate Loon 120mm fan is simply superior to the Super Red 80mm fan. The former is one of the quietest 120mm fans around... the latter is just better than average, but runs slow enough in the SS to be good.

Thanks for the info, Mike!

I've done some reading and research (including Mike's articles here) and determined that my EG425P-VE SFMA Enermax Noisetaker PSU is more than adequate for my AMD64 3000+ winchester PC with MSI Neo 2 Platinum motherboard. Other components = G400 max, 80 GB WD HD, floppy, Plextor 24/10/40 CDRW and scsi card and Pioneer DVD drive.

I believe its the CPU which can potentially use a fair amount of current on the 12v rail.

What components use the 5v and 3.3v rails? I haven't seen this listed.

thanx for any feedback

Well, most components use more than one rail.
5V & 12V - HD, optical drive, perhaps some PCI cards
3.3V and 5V - mostly PCI card I think
5V - memory, keyboard and mouse, USB, FireWire, floppy
All three rails - motherboard, VGA

Note that this is only my rough assumptions based on AMD:s "Builders Guide for Desktop/Tower Systems".

Power Supply Fundamentals & Recommended Units has been updated again. The changes are mostly on pages 2 & 3 --

-- Expanded discussion about Power Factor
-- Updated system power demands discussion
-- Added new table showing power measurements on 3 different desktop systems under various loads.

The last item should reduce the number of questions about whether a 500W PSU is going to be enough for yadayada single CPU system or should they go to 600W?

There has been much discussion on what power supplies are enough for this motherboard with 2 PCI express video cards on other sites.

I'm running one on the 400W seasonic tornado now but I would have bought a higher wattage seasonic with 120mm fan if it were available.

edit: ignore my questions. I've been reading the forumns and searching the web and the S12 looks mighty nice. I just need to decide between the 430 and the 500.

I see that the Enermax NoiseTaker 325 rated very highly, but which one did you test? The model numbers for enermax are VERY confusing because there is virtually no difference between different models\lines. Can I get the specific model number of the one you tested?

Update April 5, 2005 - Mass retirement of many older PSUs. Added Seasonic S12, Enermax Noisetaker 701, Nexus 4090. Major revisions of every part of the article.

The retired PSUs table of the last page is a mess but will; be fixed soon.

Thanks for keeping this valuable resource up to date!

Minor glitch: page 6 looks odd with many vertical black lines and only a very narrow text collumn in the right of the page.

Keep up the good work.

Minor comment:
Because the NX-4000 is retired, I think the part I put in bold is no longer as informative as it was when the two descriptions were placed right above each other.

Just wanted to say what an excellent last update this is. Top notch Mike - keep up the good work!

I also see the glitch on the final page with the vertical bars, like niels007.

niels007 & Lifecycle,
Did you see the next quote? Probably not, but it is on the frontpage too.

The last page is fixed -- it's a temporary fix, but until we can figure out the #$^%$# that's limiting the length of the articles to <11,000 "words", this will have to do. Functionally, it's as before, but the retired PSU page is actually a separate "article".

Finally, the article length limit has been removed!!!!

The recommended PSUs has been consolidated into a single article again, 7 pages and >12,000 words. Whew!

It's becoming quite an article, that PSU Fundamentals.

I'm surprised the Phantom still gets an 8+ quality rating, after all the complaints I've seen here in the forums about premature PSU death. That's the highest rating out of all the listed PSU's!

They've pretty much been all addressed as far as I can tell. AntecRep has been busting his butt to make sure that everyone here who's had a problem with their PSU has gotten a replacement.

Sometimes the quality of a PSU is not in how reliable it is, but how reliable the company that supports it is.

Yeah, SometimesWarrior, you're right, 8+ is too high for that. I better reconsider & change it.

Antec Phantom Q rating down 1 notch, reliability comments added. A few small errors fixed on page 1.

As promised in the thrread SPCR Ratings, the PSU numeric ranking system has been revised, and each and every PSU on the list has been assigned new values in the context of the new system.
http://www.silentpcreview.com/article28-page6.html

I would love to see some of the Tagan PSU reviewed and rated. I have a 480W unit that is very rearly stressed and so is extremly quiet. They are also very good value for money.

Great article on power supplies - I wish the other fanboy sites were nearly as scrupulous in technical matters re. PSUs etc.

. The proper method of calculating Power Factor is: PF=Cosine of the phase shift between the Voltage and Current wave forms in degrees.

.bh.