I've been looking at the following power supplies:

Nexus RX-6300 - £90.43 and 82% max Efficiency
Corsair HX650 - £92.40 and 85% Max Efficiency
Seasonic X-650 - £117.25 and 90% Max Efficiency (Edit - Now £105 at CCL)
Enermax Modu87+ 600w - £124.53 and 93% Max Efficiency

All claim to be virtually silent and as far as I can see, only the Seasonic has been reviewed by SPCR.
My question is whether there are any other differences between them, other than the increasing efficiency, that explains the escalating price?
(All are modular and from the same retailer - www.scan.co.uk except for the Nexus which is from www.kustompcs.co.uk)

Although my proposed new system will probably only pull 300w max I want to ensure least noise by not pushing the psu to more than 50%; so please don't use the word "overkill"
I have just about decided on the other components, with much help from this site, but the psu is a grey area. I recently put a Corsair VX-450 in my daughter's computer, as it is SPCR recommended and pretty cheap, but I find it too noisy; she doesn't seem bothered in the slightest of course! (It's an order of magnitude quieter than the Shuttle system she had before)

What would you guys recommend? I want something that will last a while with no problems. (I don't continually upgrade; I just replace everything after 4 to 5 years) Is there anything else I should be looking at? I am willing to pay top dollar for quality kit but not for a "designer label".
The case is an FT01 so the psu will get fresh air direct from it's own intake.

BTW, the Corsair HX620 seems to have been discontinued, I'm assuming that the HX-650 is it's successor?

Any advice much appreciated.

HX650 has no relation to HX620 and is made by CWT, thus a loud unit. There's no single CWT build in SPCR recommendation list, so you know the reason. Corsair's silence reputation is getting rusted when they gradually switched OEM supplier from Seasonic to CWT. Were I you, I'd purchase Enermax Eco80+ 500W instead. Though it isn't as efficient as forerunners, it is good enough 80+ and very very quiet up to 250W. It's the best one in my book considering its budget pricing and superior stock fan. Also, if you insist overkill, there's a 620W unit for your peace of mind. Having said that, I don't think noise curve would vary greatly between 500W and 620W. Or simply grab a Seasonic X-650 for fanless operation at a premium price.

SPCR reviews for your reference.
http://www.silentpcreview.com/Enermax-Eco80
http://www.silentpcreview.com/article1012-page6.html

I have bought Enermax and Seasonic PSUs. Of that list, I would go for the Seasonic X-650. Enermax PSUs get good reviews, but there have been too many reports of noisy fans on previous models for me to suggest them over the Seasonic. The Seasonic is a premium product, but it will be very quiet. And the extra cost over the cheapest on your shortlist is not excessive in the context of the overall system cost.

The 'overkill' issue is constantly raised. When buying my last PSU I took a long and careful look at the shortlist, and ended up buying the one with the highest rating. The rating was approximately the maximum power draw x 2. The reason was that PSUs are typically at their best, in terms of efficiency and quietness, at around 50% of their nominal capacity. If you run at 60% or 70% as some of the 'just enough' school advocate then you don't necessarily get either. And I think you've some practical experience of that already.

Thanks, but I'm only looking at modular versions.
Does anyone know whether the Nexus 5300/6300 is as quiet as the Nexus 5000? - according to the review here, it is as quiet as the X-650 at 250W.

You could take a look at the Be-Quiet Dark Power Pro series, judge. I'm using the 650W version, a superb unit.

It's housed in an Antec P183.

I have no experience with the latest offerings from Seasonic and Corsair and I've never used units from Nexus, so I cannot comment on those. let alone make suggestions.


/good luck

Actually, that was my original choice - however I came across a couple of reviews (and a post here on SPCR) that suggested that these power supplies were prone to blow up and that the caps were rated at a lower temperature than other quality power supplies. A review on JohnnyGuru.com would be useful; that site seems to be the bible of power supply reviews.

Strange really because I have always regarded German engineering highly. (My car and all our kitchen appliances are German and very reliable) Whether or not these are actually made in Germany or elsewhere, I don't know.

The HX620 may have been discontinued, but there are still some available from ebuyer for £90, if it's of any help to you.

http://www.ebuyer.com/product/114941

Exactly. Given the time and effort people put into making their computers quiet, it doesn't make sense to me to skimp on the psu.
The extra cost of a higher power psu, say £50, when spread over a lifespan of 5 years is a tenner a year. That's a beer and a packet of ciggies. Besides, I saved more than that by getting the case second hand off e-bay!

Thanks for the tip, but I think it's getting a bit dated now. At 250W output the SPL is 22dBA vs 14 dBA for the X650 and Nexus 5000, according to SPCR reviews. The efficiency is well down as well.

I'm drawn to the Seasonic X650 but if the Nexus RX 5300 proved to be as quiet as the Nexus NX 5000 I would go for that. (I've been using a Nexus 400w "Real Silent" psu for just over 5 years now with no problems - and it is the only exhaust fan in the case. (Nexus Breeze)

The "overkill" thing comes from people thinking they really need a powerful PSU, when they don't. While there is some truth to the more powerful ones being more efficient, that doesn't necessarily mean that they're quieter. They can have a really bad fan ramp up curve, or just a fan that makes more noise to begin with. That's why I suggest you just ignore the wattage, and instead look at the comparison table from the Nexus review that was linked. Check the column for your peak expected wattage, and then see if there's a sudden ramp/jump in noise.

I also suggest you not get anything that hasn't been tested by SPCR, simply because there so much that can vary from model to model, and it's impossible to know if they'll perform well or not without independent testing.

That's exactly what I have been doing - for weeks.
Incidentally, most PSUs do seem to achieve max efficiency at around 50%, as lodestar pointed out, which is why I am looking at 600w units and not 850W or more!



That's very sound advice and the reason that I was after more info on the Nexus, Corsair and Enermax in my original list.
Good example is here: compare the Nexus NX-5000 with the Nexus RX-8500. The results are the opposite to what one might have expected, given their relative power ratings.

I have of course read reviews on other sites which tell how quiet they all are but those sites are not SPCR! Some test with an ambient of 25dBA.
I also have the valuable advice from "loimlo" in this thread that the HX 650 is totally different to the HX620 and have as a result, rejected it.

Anyway, I've got another month before I get back home to build the thing, hopefully in that time there will be some reviews here of some of these newer units.[/url]

I took the time spending a couple of hours trying to find something on the Dark Power Pro series which would suggest poor caps but so far I have been unable to find anything. Could be that this is an issue reserved for Be-Quiets Straight Power series, but I'm not sure.

Perhaps this goes against better judgment, but the unit stays for now. I'm so pleased with its performance and lack of "intrusion" that I cannot bring myself to yank it out, especially so since I cannot seem to find anything which would directly fault it.

The Modu87+ was reviewed by anandtech and it's fan spins at only 330 RPM up to 500W so it should be really quiet, possibly as quiet as it gets with a fan. The X-650 is a great PSU though and in addition to the high efficiency och semi-passive cooling design it also performs great with ripple and voltage-regulation in a league of its own.

If you'd decide to go with Nexus, make sure it's a new model SPCR has reviewed because all of them aren't that quiet.

In that case, you're left with the Seasonic X-650, simply because it's the only one on your list that's been reviewed. At 300W there's hardly any ramping, so you should be safe in getting it, provided you're not planning on going for a dual video card setup or something similar at a later point.

i agree with flinx, i had the exact same ideas as you and received the x650 3 days ago. not a pep since, 100% modular, gold, using about 25% of cables included, nice and neat.

-AMD Phenom II X4 965 Black Edition Deneb 3.4GHz
-G.SKILL Ripjaws Series 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600
-ASUS M4A785TD-V EVO/U3S6 AM3 AMD 785G
-2 Western Digital Caviar RE 320GB 7200 RPM 16MB Cache SATA 3.0G
-lite on IDE dvd burner iHAP422-08
-creative SB X-FI audio 9400
-1 120mm
-memory card reader/writer
-antec solo case

The only concern is fan choice: 139mm fan in Modu87+. It may be louder than excellent 120mm fans in Seasonic X650 and Enermax Eco80+ at similar RPM level. So I'm also for Seasonic X650 if it were to be compared to Modu87+.

Sorry if I alarmed you Walle!
I did bookmark one of the reviews that I was thinking of - here - but on re-reading it, maybe they have sorted the problems. I can't remember where the others were and I don't have time to hunt for them at the moment. Perhaps the person that posted in this forum (my previous link) had one of these earlier versions or was just plain unlucky.
Anyway, it's good that you are happy with yours.

I really doubt the Eco would be as quiet because it's not in the same quality and hotter, fan speedup occurs earlier as well. The Modu87+ won't speed up until 500W load so for a high power computer it's probably more quiet than X-650 as well. Anandtech also measured it's acoustic noise to be the lowest they've ever measured so it can't be that bad.

I should add that if you are not in need of the 600+ Watts it's really unnecessary to choose a super high end PSU such as X-650 och Modu87+. Why won't you buy a VX450 and just swap the fan?

I don't want to sound ungrateful, but did you read my first post?
Or Lodestars reply?
Apart from those factors already mentioned, I do not want to open up a brand new psu and void the warranty in order to swap out a fan.

No worries Judge, good luck with your build.


Edit:
Judge, while reading the review you linked to I stumbled upon this.

double post. :/

While the modu87+ do look very good, they're rather expensive. Here's the mentioned Anandtech review for reference:

http://www.anandtech.com/casecoolingpsu ... i=3723&p=1

Interesting - The Antec TruePower New TP-650 wins out over the X-650; it's also made by Seasonic and is a lot cheaper... if only I hadn't read AndyB's rant about Antec's (lack of) customer support.

Just need a review by MikeC now. I wonder what's in the pipeline??

Anyway, many thanks to all who have offered advice and links!

I am completely satisfied with my Nexus R5300. Dead silent. Would recommend highly.

caveat: I have maybe not stressed it much, so the fan may not have spun up much at all. But, that was why I got this. I designed my system to be high speed but low cooling needs.

I wanted modular also.

Dave

I don't see a noise test, so I don't understand how it would win anything.

here you go, have at it. not all reviews are the same .

http://hardocp.com/reviews/psu_power_supplies/

Perhaps I should have been more precise-
The Antec got a higher overall score than the Seasonic in that review mainly because it was considered to be better value for money. As far as noise goes it seems that only subjective impressions were noted:


At the moment, for me, it's between the X-650 and the Modu87+ 500W; both of which are available for around £105 in the UK. I would love to see a review of the Enermax here at SPCR though...

Hey all, Just signed up to forums.

Im confused. Im trying to organise parts from a pc (i5 3.2ghz, 4gb ddr3 1333, sata2 500gb HDD, gigabyte p55-usb3, ati 5770, lg blue ray, antec 900 case, win 7) and all that remains is the power supply.

These are the power supplies available to me...
http://www.netplus.com.au/products-list ... 20Supplies

I read review on hx620 on spcr and thought that would be perfect (similar to original poster im happy to have large margin i know 650W is to much)

I read review on hx620 and was sold on hx650 but then read Ioimio post about different OEM and had wind kicked out of me. I read reviews on antec true power550W and Coolermaster Silent 700W and they seem to get expenetionally louder at 250+W

Anyhow i went to these sites
http://whirlpool.net.au/wiki/?tag=PSU_manufacturers
http://forums.hexus.net/1624441-post17.html
http://www.tomshardware.com/forum/25931 ... e-seasonic
http://forums.whirlpool.net.au/forum-re ... 80169.html
and they all say the HX650W is still made by seasonic???? Was original post incorrect.

Because while spcr hasnt review hx650 yet corsair has this on their site...
http://www.corsair.com/products/hx650/hx650-N-chart.png
suggesting its quite over 325W

I really wanna be able to get the corsair PSU if its reliable cause it will slot nicely into this rig

Thanks in advance for replies Sorry to hijack your forum judge56988

No problem - the more input the better!

You can't trust the fan ramp up curves at Corsair - they lie. The VX ones in particular are just completely wrong. Here's an old chart from SPCR:

http://www.silentpcreview.com/files/ima ... _power.gif

I guesstimate that with a 5770, you could hit peak loads of around 250 W. That gives you a bit of choice, but if you ever go for a higher load (say ATI 5870 instead), you might regret whatever you picked.

The CM Silent Pro 500/600 did get pretty good results for noise at anandtech by the way:

http://www.anandtech.com/casecoolingpsu ... spx?i=3402

They're not the same design as the 700W that was tested here at SPCR, so it's very possible that they're an improvement in that respect. Just keep in mind the short cable length (40cm for 500W, 45cm for the 600W)