SPCR

Hi,

I've been looking for a low-power, semi fanless PSU, similar to Corsair RM450 but around the 400W mark (and preferably cheaper too). I want it to run completely fanless under light load, which will be the case for this PC for most of the time. Does such a thing even exist?

I've also been looking at the Seasonic G-450, more for its price and modularity than for its power, but I couldn't find anywhere comments about how if performs acoustically. Does anyone have some first-hand experience with this PSU?

Thank you in advance!

kufi wrote:I've been looking for a low-power, semi fanless PSU, similar to Corsair RM450 but around the 400W mark (and preferably cheaper too).

AFAIK there are probably none but the Seasonic X-400FL, at least in ATX form factor, and it isn't cheaper.

But there are some very quiet fanned ones, like the BeQuiet E9, around the 400W mark, or a bit less likely, the L8 and System 7 series down to 300W.
Around the 350W mark, once there were the Enermax ErPro/Liberty and Pro82+: they are now discontinued and i don't know whether the current Triathlor are as quiet as them, or not.

Within TFX and 1U form factors there are several Seasonic 80plus Gold models, but you may need a more suitable enclosure.
Even better, if your demanding power isn't too much high, perhaps you may think to PicoPSU and the likes (from about 60W, up to around 190W).

Thanks for your reply

quest_for_silence wrote: AFAIK there are probably none but the Seasonic X-400FL, at least in ATX form factor, and it isn't cheaper.

I'm trying to avoid the Seasonic X-400FL, firstly because of its price, but also I plan a rig with passive CPU cooling and the node 304 (the chosen case) the intake fans are above the PSU level, and the exhaust fan is too far from the PSU to 'pull' out the heat efficiently (IMHO). I'm afraid that heat rising from the PSU will slow-cook my storage devices that hang above it. Otherwise, it's output, size and modularity are absolutely fantastic for this rig, and if you think that the airflow in the case will suffice than I might just dig deeper in my pocket and find the extra couple of dozen € that it costs here.

quest_for_silence wrote:
But there are some very quiet fanned ones, like the BeQuiet E9, around the 400W mark, or a bit less likely, the L8 and System 7 series down to 300W.
Around the 350W mark, once there were the Enermax ErPro/Liberty and Pro82+: they are now discontinued and i don't know whether the current Triathlor are as quiet as them, or not.

For a reason that I don't quite understand, Be Quiet! low-power PSU are really hard to get here in Finland. I've read reviews Be Quiet units (I think the E9 was one of them) but if I can't get them easily than I'm gonna have to skip.

quest_for_silence wrote: Within TFX and 1U form factors there are several Seasonic 80plus Gold models, but you may need a more suitable enclosure.
Even better, if your demanding power isn't too much high, perhaps you may think to PicoPSU and the likes (from about 60W, up to around 190W).

I am only looikng at ATX solutions, but thanks for the suggestion.

How are the low power Super Flower Pro units in terms of acoustics? If I understand the reviews right, than their fan and fan controller are superior to the Seasonic G-series. Any thoughts?

kufi wrote:How are the low power Super Flower Pro units in terms of acoustics? If I understand the reviews right, than their fan and fan controller are superior to the Seasonic G-series. Any thoughts?

Well the Pro I know are a fixed cables version of the Golden King platform, or so about: given that, they should be far better than any G-series, but AFAIK they have also been discontinued; moreover, I don't think there was any SuperFlower Pro around 400W or less.

At any rate, currently I don't see any drawback going for an X-400 with the top grille facing downwards: the bottom will be the intake, the side the exhaust, and in case you might use some foot (something like the Nexus ones) to elevate a bit the enclosure (but to be fair I think it shouldn't be necessary).

kufi wrote:I've also been looking at the Seasonic G-450, more for its price and modularity than for its power, but I couldn't find anywhere comments about how if performs acoustically. Does anyone have some first-hand experience with this PSU?

I found two reviews, which judging by their descriptions, the G-450 may not be up to SPCR standards. :
http://hardwareinsights.com/wp/seasonic-g-450-review/3/
http://www.hardocp.com/article/2014/04/ ... y_review/6

I also found two comments in viewtopic.php?f=6&t=64885&start=150:

jerdenberg wrote:Based on all the positive comments, I bought two G-450 power supplies, but both of them produce the worst hum I've heard in years. In fact, the hum is the only sound I hear from under the desk where the pc is located. As replacements for Nexus value power supplies, they are complete failures.

jerdenberg wrote:At first I thought it was electrical, sounding more or less like the transformer hum of old, but with the power supply on my desk and running without a load, I get the impression it is produced by the fan, especially as the hum comes on when the fan spins up after switching on, and fades when the fan spins down after switching off.

In addition, there is another sound that is a little difficult to describe: I suppose it cannot be called ticking, but it is related – like (a very low-level version of) the sound of a diesel engine at low rpm.

quest_for_silence wrote: Well the Pro I know are a fixed cables version of the Golden King platform, or so about: given that, they should be far better than any G-series, but AFAIK they have also been discontinued; moreover, I don't think there was any SuperFlower Pro around 400W or less.

I guess it really has been discontinued, but probably some shops still stock them:
http://www.jimms.fi/tuote/SF-400P14XE-PRO
(don't mind the Finnish...). At this price, if it's as good acoustically and performance-wise as you say, it's probably a bargain. I can't find any unit that is silent AND modular AND <400W at this price level.

quest_for_silence wrote:
At any rate, currently I don't see any drawback going for an X-400 with the top grille facing downwards: the bottom will be the intake, the side the exhaust, and in case you might use some foot (something like the Nexus ones) to elevate a bit the enclosure (but to be fair I think it shouldn't be necessary).

The rig I am planning will have (most likely) a passive CPU cooler and will rely on the case fans alone for ventilation. Will it not be too much to also stick a passive PSU in there, as efficient as it is?

yakuman wrote: I found two reviews, which judging by their descriptions, the G-450 may not be up to SPCR standards. :
http://hardwareinsights.com/wp/seasonic-g-450-review/3/
http://www.hardocp.com/article/2014/04/ ... y_review/6

I also found two comments in viewtopic.php?f=6&t=64885&start=150:

jerdenberg wrote:Based on all the positive comments, I bought two G-450 power supplies, but both of them produce the worst hum I've heard in years. In fact, the hum is the only sound I hear from under the desk where the pc is located. As replacements for Nexus value power supplies, they are complete failures.

jerdenberg wrote:At first I thought it was electrical, sounding more or less like the transformer hum of old, but with the power supply on my desk and running without a load, I get the impression it is produced by the fan, especially as the hum comes on when the fan spins up after switching on, and fades when the fan spins down after switching off.

In addition, there is another sound that is a little difficult to describe: I suppose it cannot be called ticking, but it is related – like (a very low-level version of) the sound of a diesel engine at low rpm.

Thank you very much for those references. The reviews actually rate the g-450 as 'quiet', however this comment you attached is really making me want to avoid this unit

kufi wrote:Thank you very much for those references. The reviews actually rate the g-450 as 'quiet', however this comment you attached is really making me want to avoid this unit

Don't mind me . It's just based on my observations of various review sites that their definition of quiet is typically far from SPCR's definition . Of course, it also depends on your tolerance level.

yakuman wrote:Don't mind me . It's just based on my observations of various review sites that their definition of quiet is typically far from SPCR's definition . Of course, it also depends on your tolerance level.

My tolerance was rather high, having been working in huge data centers back in the days, but my last 2 pcs were 'Noisy and Noisier' and I can't stand it anymore (both were standing on my desk and the new one will too). It had reached a level that we shout at each other just to be heard over the constant buzz around, or having to set the volume on TV so high that it wakes our kids up so...enough is enough

kufi wrote:Will it not be too much to also stick a passive PSU in there, as efficient as it is?

AFAIK the PSU has no evacuation role in an ATX setup: IME/IMHO the X-400 can work in it, and it won't hurt. Besides, a semi-fanless PSU would act about the same.

quest_for_silence wrote: AFAIK the PSU has no evacuation role in an ATX setup: IME/IMHO the X-400 can work in it, and it won't hurt. Besides, a semi-fanless PSU would act about the same.

That's a good point, of course. Only thing is that I'm planning to build the PC inside a Fractal Node 304 and not a proper ATX box, and that's why I'm concerned about the cumulative effect of 2 passive devices in such a small box. I will also say that IMHO if, by using a fully fanless PSU, I will have to set all my case fans on 'high' than I've achieved nothing, as they will be too audible.

kufi wrote:I'm concerned about the cumulative effect of 2 passive devices in such a small box. I will also say that IMHO if, by using a fully fanless PSU, I will have to set all my case fans on 'high' than I've achieved nothing, as they will be too audible.

I'm not a fan of the fully fanless setup, but an ATX PSU like the X-400 is not an heatsink: and above all, with reference to your concern, all semi-fanless PSUs would be exactly the same, so the solution is not using an hybrid PSU, but mounting any PSU with the upper grille facing downwards (otherwise why - according to you - the 304 has an intake on its bottom right under the PSU itself?).

About the case fans, there's no need to drive them at full speed, even with two passive components: obviously, you can't expect to have very low temperatures, but let me say that's the norm for any really quiet rig.

quest_for_silence wrote:...but mounting any PSU with the upper grille facing downwards (otherwise why - according to you - the 304 has an intake on its bottom right under the PSU itself?).

Thanks for the helpful comments, much appreciated.
I don't understand something quite fundamental, so excuse me if this is a lame question: assuming the heat from the PSU is rising up, wouldn't mounting it upside down cause the heat to stay in the vicinity of the PSU circuits? Why not using the case fans for moving away the hot air around the PSU? (I clearly remember reading something about this in some fanless PSU review, but I didn't understand the idea back then either..).

The amount of heat from a passive PSU would be what? 10W? In a passive setup that might tip the scales, but you have case fans man! Two 92mm intakes and one 120mm outtake? There will be no slow buildup of heat rising from the hot PSU, it will be whooosh! and away even with the fans at a low setting.

kufi wrote:assuming the heat from the PSU is rising up, wouldn't mounting it upside down cause the heat to stay in the vicinity of the PSU circuits?

Well, IME/IMHO it would look like a somewhat rough simplification: first of all, as air is a gas, then it will go through wherever it can, so through the back/side panels, which are at a convenient height from the case bottom, and not stay there.
What it's true, indeed, is that PSU will arrive wrapped into a warning sticker saying to mount it with the top grille facing up (without saying a word about why and when): in my experience (I own a 460 and a 750) it doesn't matter mounting the PSU either facing up or down (they are all alive'n'kickin after some years) but, you know, that's just my personal experience.

Then, as said by Vicotnik, you must specify how much wasted heat would stay there (at most the X-400 should waste about fourty W, however). Eventually, we can't assume that the air is stagnant, because a starving airflow is secured even by three slow running case fans.

Last but not least, as IMHO there should be about a little difference mounting that PSU straight or flipped, whether your primary concern is to lower the hard drives temperature, more probably that not you should mount *any* fanless or semi-fanless PSU facing downwards (to be honest, IMHO that requires also some testing, in order to determine whether an 80Plus Gold PSU orientation may significantly impact the hard drives temperatures, which usually mostly depend on the drive itself).

Summarizing, IMHO: regardless of PSU orientation, there's no worry about heating the PSU itself under any reasonable usage conditions (such as up to 30 hours continuatively at high to full load without any ventilation, as that's how SPCR tested the X-400), and there could be very little about heating the hard drives, which could be somehow addressed facing downwards *any* fanless or semi-fanless PSU.

kufi wrote:Why not using the case fans for moving away the hot air around the PSU? (I clearly remember reading something about this in some fanless PSU review, but I didn't understand the idea back then either..).

Because in the specific case of an high quality 80Plus Gold rated unit, there's about no need, providing your primary concern is to keep as low as possible the hard drives temperatures. Obviously, it won't hurt, either: definitely, IMO you may mount it as you may rather (as you should get comparable results).

Thanks again for all the replies, I now know more about power supplies than I ever did.

However, for the past 2 days I've trying over and over again to play with my build budget, and no matter what I try, a fanless PSU just doesn't fit in.
It seems like I'm gonna have to go with either SF Golden Green Pro 400w, BQT Straight Power E9 400w or Seasonic G-360. Not sure if any of them is significantly better than the others, but my hunch tells me to take the Be Quiet unit (which is sold here after all). Hopefully I won't be disappointed.

Happy Easter!

kufi wrote:Hopefully I won't be disappointed.

Happy Easter!

Happy Easter to you, kufi.

Well, before making the final choice, just check the cabling lenght also, as inside a 304 you will not have so much space.
A Corsair RM450 has modular flat cabling, while the E9 400 is not modular, even if I also think the relevant prices are far from being comparable.
The same considerations also apply to Seasonic G-360, and to what you call "Golden Green Pro", which I never heard of (so YMMV about this latter, even if I think it should be a regular Golden Green, already tested by SPCR).

quest_for_silence wrote: Well, before making the final choice, just check the cabling lenght also, as inside a 304 you will not have so much space.
A Corsair RM450 has modular flat cabling, while the E9 400 is not modular, even if I also think the relevant prices are far from being comparable.
The same considerations also apply to Seasonic G-360, and to what you call "Golden Green Pro", which I never heard of (so YMMV about this latter, even if I think it should be a regular Golden Green, already tested by SPCR).

Thanks for the warning. I am actually aware of this issue and pretty bummed from selecting a PSU that will no doubt make a complete mess of of my (hopefully) neat build.
The RM450 is about 90 euro here, so not such a big difference from what I was hoping to spend. The Be Quiet Straight Power E9 480 CM is also an option, but with even higher (totally redundant for my needs) output, and slightly more expensive. Maybe it'll be the Corsair after all...