I'm glad to see a bequiet! PSU review. Looks like I can add 'em to my suggestions to EU PC builders. Very pretty, indeed. I searched around for the 650W version's efficiency data and it's curve aligns with the 550W. So maybe they are just slapping the 550W labels on the 650W design.

Nice grille design. Can't say that's something you'd expect to say about a PSU.


Should be casual, not causal?

Nicely done curves,Steve... (uh want to do a little probono excel work for SPCR? ) butit could also be just a testing error either on my part or my PSU load test rig. With so many other review sites now using electronic automated PSU test loaders these days, I can't claim higher accuracy. I still look from time to time for apro lab quality PSU tester which allows the internal cooling fans to be turned off, but this just doesn't seem to be an option on any of them. Gotta build one if I want better accuracy & any kind of automation.

But back to the bequiet DPP10 550W -- I was very pleasantly surprised, a lot of hyped up products end up disappointing.

Nice results. I'd love to see a review of the less expensive E9 400W (still 80+ Gold).

I'm not going to sweat over a percent or two of efficiency variation in test results between review sites. (That said, the 21.4W DC result of only 65% is suspect. ) The big draw here is always going to be accurate noise testing that resolves down to 10dBA.

Also, props to FSP's high power factor throughout the power range.

FYI: The price tag on the first page of the review (and noted in words) is before VAT (value added tax (a percentage)) which in the UK is 20% - that £90 PSU is in reality a £108 PSU.

Its bit brother (650W model) is available here (not that I am endorsing this particular eTailer for my own benefit) for £124 (including VAT) which is somewhat over the odds.

http://www.ebuyer.com/search?sort=price ... =10&page=1

They have a total of 22 BeQuiet PSU's for sale, I do note 2 things, they appear to be above average price and above average quality and for the ones that I have looked at (check for yourself) they have a 5-year warranty which is very reassuring (presuming that you dont have to send one to Germany to be replaced).

As someone earlier mentioned, I would really like to have a look at their lower models such as the aforementioned 400W model.


Andy

From Scan UK the 550w is £99 including VAT (sales tax) which is a better deal but still makes it one of the most expensive 550w PSUs on the market. The additional features that mark out the Dark Power Pro models are fairly obvious but I struggle slightly to understand what the difference is between the BQ Efficient Power and Straight Power ranges. BQ also seem to have PSUs at quite small power increments within their ranges, for example in the Straight Power Gold range between 400w and 600w there is a choice of 400w, 450w, 480w, 500w, 550w, 580w and 600w units.

This is the absurdity I rail against!

Well spotted, Scan is one of the 8-12 eTailers prices I often check ( I did not check).

It is still expensive, but it has a 5-year warranty, and that counts for a lot (so long as the shipping costs are not too much) adds to its value to a degree.

Personally, I would not but anything above "Bronze" right now because the savings gained don't add up to the extra cost of Silver, Gold, Platinum (is Diamond next, think wedding anniversaries) vs the amount that is saved in electricity.

If Bronze and Gold got closer in price at the 500W and (below that) with 3+ year warranties I would look to buy them.

The standard PSU I use in PC builds that I sell to people is the following.

http://www.ebuyer.com/271798-corsair-43 ... -430cxv2uk

It doesn't break any records, but it "ticks" every box it needs to.

3-year warranty, quiet (not SPCR), reliable, enough power for almost any non-gaming build, enough SATA connectors to be used for most serious storage needs. This is £36 almost 1/3rd of the cost of the reviewed 550W model, I know its not directly comparable, it only a bronze PSU, its only 360W it only has a 3-year warranty, and its not even modular. When BeQuiet or anyone else brings out a PSU that is better than the one I am using and "proven" I will swap the PSU that I use in my PC builds, until then, "cheap" Bronze wins over expensive gold every time - especially where warranty and reputation counts.


Andy

With most DIY PC builders, choosing components is rarely such a straight-up, rational, cost-conscious process.This is probably true for most discretionary purchases.

I always consider PSU efficiency for 3 reasons -- it means less heat for the computer to deal with, probably will last longer as a result, it's usually quieter, and it is usually more ecological. Re- the eco factor: It all adds up, every little bit. The reduced electric bill is the last thing on my mind.

One other simple factor: Highest efficiency now = highest quality. The best quality PSUs are almost invariably the highest efficiency now. So if you want quality...

The Seasonic G Series will help to compress the price differences between Bronze and Gold rated supplies. I expect other mfgrs will follow soon. I see current pricing of $60 for the G-360 and $85 (after MIR) for the G-550. That covers most builds. The M12II 520W goes for $70, so for $15 more you get Gold.

I use my PC for about 8 hrs a day (although today looks like 14 ). About 6 hours effectively idling/low stress and 2 hours gaming. When it's not in use, it's sleeping and using ~ 1W. Based on my use pattern and ~$.13/kWH, it costs me ~$45.50/yr in juice with my Bronze rated PSU. If I had built with a Gold rated PSU, I'd have saved ~5% in power, or $2.28/yr. Over 5 years, it's $11.

So, it doesn't payback in the wallet, but for $4 more over those 5 years, I get a cooler running and quieter setup. Oh, and if I lived in Silicon Valley rather than in a coastal town, I'd need air conditioning. My electrical use would pop me into a higher tier of $0.24 to $0.36/kWH. Over 5 years, that's $20 or more in savings for the Gold vs Bronze.

Well, over here the G-360 sells for 60€, the G-550 for about 100€ including taxes, not including shipping costs. And we do not have any MIR

@Andy: The only reasonable other psu could be a be quiet! Pure Power L7 350W ATX 2.3. Costs about the same and, as i have build a few systems with that one, it at least matches Corsairs modell, might be a tad quieter, but both are absolutely comparable.

Recently put their "Straight Power" E9 480W modular into a recent partial upgrade. From a purely subjective perspective my ears comprehend this as similarly inaudible at normal operating ranges (73 watt i3-530, c.80 watt HD7770 graphics). As best I can tell, the Straight Power range keep the noise characteristics of the Dark Power range but lose the 12v rail switch and built in fan controllers. The Pure Power base range appears to be significantly different using different fan sizes and mounting though.

Straight Power E9 480w modular was at aria.co.uk at £78 uk (including 20% VAT).

Titanium is the next one but it is only standardised for 230V server supplies at this point in time:
http://en.wikipedia.org/wiki/80_Plus

We are getting to the point of diminishing returns in terms of advancment of PSU efficiency. The big gains have already been made. However, it does still mean that as a percentage the level of heat generated in the PSU can be greatly improved as a proportion still. An 80+ Titanium PSU will produce only two thirds of the heat of an 80+ Platinum PSU at 50% load (96% eff. vs 94%) so we will see more passive running. I do however note that the 100% load efficiency remains the same at 91% so maybe we not not see much improvement at max load.

Maybe the big gains to be had now will be from the trickle down of the technology such that there are more Gold rated smaller wattage units like the G-360. There are also a few SFX sized Gold units out including a crazy 450W modular one from Silverstone. There are also some passive 1U server supplies appearing. Perhaps with a bit more shrinkage of the heatsinks required we will see passive SFX, TFX and other small form factors before too long.

Now that's more like it. After the lackluster cooler, this is a real bombshell of a PSU. Just hoping the price stays reasonable.

I'm not sure how I feel about a PSU controlling fans, but it's good to have that option, in case it lies in its own compartment or has a dedicated fan for airflow. For me the days of hardware fan control are over. The rail switch I don't even know what I would or could do with.

You think that's bad?

Try 70 € for the 360W and 120 € for the 550W.

At last, I get to see a bequiet! psu reviewed here. If any of my psus ever die, I will definately consider this now for my next build.

Hello,

Long-time reader here.

I bought the Dark Power Pro 10 650W after reading Mike's review. The fan was inaudible in my near-silent system, but it buzzed under light and medium loads -- for example, while booting Windows or scrolling the browser window. The buzz was (barely) audible from 2 meters away in a closed, well-dampened case (Fractal Define R4). I would compare the sound to that of a fly caught inside the PSU, or the seek noise of a hard drive.

There was no buzzing under full load and in idle. Putting the CPU (i5 3570K) on fixed voltage alleviated the sound a bit, as did disabling the C1E power saving mode, so I assume it has something to do with the rapidly changing power requirements of the CPU. GPU load seemed to have no effect on it.

I temporarily transplanted an old Corsair HX520W from my other PC and it's dead silent regardless of the load (except for a slight buzz when I put my ear to the PSU).

I decided to return the unit to the store (thank God for distance selling regulations) and I'm currently waiting for the Straight Power C9 580W from the same manufacturer. If that one also has the buzz, I'm going for something cheaper and less efficient.

I have a hunch that the recent plague of electrical noise in high-end PSUs has something to do with the rising efficiency -- I don't remember any talk of whining and buzzing PSUs before this whole 80 Plus Gold/Platinum craze came along... I for one would rather pay a slightly higher electric bill than have to deal with some insect-like noise every time I move my mouse!

Anyway, I just wanted to put this report out there for the benefit of those considering the BeQuiet Dark Power 10. If you're hoping for total silence, you may want to look elsewhere.

BTW, I would like to thank Mike for this site. I always check SPCR before I buy new gear.

What motherboard are you using? Are you sure it's the PSU and not the motherboard?
I've got coil whine from my motherboard with a Pentium G620 on an Asus H61 board with a BQ Straight Power 400W.
I've also got coil whine from a Sapphire Radeon 7950 on an Asus Z77 board with an Antec PSU.

I guess I should try a PSU swap.

Would you recommend this PSU over the Seasonic X or M12II series?

There's probably some truth to this hunch, but OTOH, I recall the dark pre-80% efficient days when I swapped out fans to make PSUs quieter, the question of electrical noise audibility would often come up. There are powerful psychoacoustic effects that make whining & buzzing much less audible when accompanied by the broadband turbulence of airflow noise. Today's ultra-efficient PSUs all run extremely slow & quiet fans -- because their cool running allows it -- which make them far more liable to exhibit electronic noise unmasked by white/pink noise. Manufacturers haven't quite figured out that this can be even more annoying than fan noise... and how to prevent it consistently.

You're welcome.

Definately better than the venerable M12II Bronze.

Seasonic X has better efficiency (and 5W better at idle), BeQuiet! has a nice fan profile and the external fan header.

I was deciding between these 2 because I wanted the quietest one. I can only get the Seasonic X @ 650w but I can get the BeQuiet at 550w. I don't really need the 650w to run my i5 2500k @ 4ghz and GTX580 system.

I've just replaced a Seasonic X-650 with the Dark Power Pro 10 550W.

I did this because I've tried to quieten all sources of noise in my PC: changed hard-drives to 5400rpm ones, bought a quiet graphics card and used slipstream fans in my case. Yet I was left with a dull humming noise which I couldn't eliminate. After reading the Dark Power Pro 10's review on SPCR, I thought I'd take a chance replacing my Seasonic X-650 and this seems to have solved the problem.

Before my PC was very quiet - now it's almost silent. I was surprised that the X-650 was the cause of the humming because I bought it because of its low noise profile, but am now very pleased with the Dark Power Pro 10.

The other good thing about this PSU is that I only have two fan headers on my motherboard (one of which controls the CPU fan), so I can use this power supply to control my four case fans. Also it looks great and is reassuring heavy and well built (as well as just about silent).

Do you have any control over those fans or is their RPM linked to the internal PSU temperature?

Mike,

Thanks for sharing your perspective on electrical noise. I'm sure all PSUs have some amount of electrical noise, but it seems that nowadays there is a much larger number of units that can be heard from 1-5 meters away.

The quietest PSU I have owned is the Corsair HX520W (bought it after reading the SPCR review). Very quiet fan and ZERO electrical noise. I have tested it in various configurations, and no matter what I do, I can't make it buzz or whine (except if I hold my ear to the PSU). Why do you think it's impossible to buy a PSU like that today, no matter how much you have to spend?

I also don't recall any electrical noise problems with the PSUs I owned before (a 400W Tagan and a 350W Chieftec), although they were both used in quiet PCs.

Best,

Tomasz

Asus P8Z77-V Pro. Yes, I'm sure. The mobo is dead silent, as is the video card (MSI HD7850).

Well, I exchanged the Dark Power Pro 10 650W for the Straight Power E9 580W, which is beQuiet's midrange model. Initially, it seemed that the Straight Power had very little buzzing -- the loudest buzz I was able to generate was audible from a feet away (the Dark Power's buzz was audible from 2 meters away).

However, when I plugged in my Dell monitor, the PSU started buzzing quite loudly. It is a constant sound, independent of system load. I tried plugging in other devices (monitors, laptop PSU, etc.) to the same AC circuit, but only the Dell display makes it buzz. Which is a problem because the Dell is my main display!

Does anyone know what's going on? Would a surge protector help? Would be grateful for any insights.

Tomasz

RFI interference and/or bad power factor noise getting back into the mains? The PSU for the Dell monitor may be causing a reaction in the computer PSU via one of those, quite possibly.