Be Quiet Dark Power Pro P8 1000w Review Page: 1

Be Quiet P8 1000w ATX PSU

Be Quiet have been in the UK for a couple of years now, and in that time have managed to woo us with some pretty special power supplies. Most memorable of all has to be the original Dark Power Pro 650w that literally took the media by storm and became one of the most awarded PSU's of 2008.

Now in 2010 things have changed and many manufacturers have upgraded their PSU's to suit the needs of the energy concious consumer. 80PLUS Gold/Silver/Bronze level efficiency has been introduced, and the launch of Nvidia's Fermi GPU has once again rekindled people's interests in the high-wattage end of the market.

Keen to keep up with the game, Be Quiet have launched a new revision of their Dark Power Pro series going simply by the name of 'P8'. Today I'm going to be checking out this new kid on the block to find out whether it is a worthy successor to the Dark Power Pro throne.

Let's start with the specs...

Follow your heart.

This heart opens up unexpected worlds.

Those who have big goals in sight and who put intense demands on themselves and their equipment during professional graphics work or extreme gaming situations will redefine their limits, starting now: with Dark Power Pro P8, the superlatively powerful and efficient computer heart from be quiet!. The new generation of Dark Power Pro P8 is at home in the high watt range, helping anyone who wants more to make a decisive step forward. Starting immediately, the Dark Power Pro P8 universe now contains four models (750W, 900W, 1000W and 1200W) demonstrating (with) up to 92% efficiency (at 230V), earning them 80 PLUS® Silver certification. With Dark Power Pro P8 you′ll experience top performance up close and personal: Powerful, reliable, efficient and above all: quiet.

We′ve equipped Dark Power Pro P8 perfectly for your tasks: multi-GPU ready with up to six PCIe connectors and up to six 12V rails for stable power. The innovative Overclocking Key opens up new dimensions through the manually operated combination of all 12V rails into one single 12V rail. The especially user-friendly cable management system provides you with up to 37 different connection options. The flexible cable exit and sleeved cable protect against ruptured cables. The prize-winning 120mm SilentWings fan provides the quiet operation for which the be quiet! line is known. The high-quality metallic coating and harmoniously rounded corners lend the new Dark Power ProP8 a distinctive look as well. Dark Power Pro P8: this is how your heart beats.

Wow, some very powerful words. Almost brought a tear to my eye. But seriously, this is a power supply we're talking about here Be Quiet, not a new £100k sports car. "Follow your heart"? Surely that's just another way of saying "don't use your brain"? Anyway, the actual bulk of the specs was so wordy that it would have taken up a good two pages of the review, so instead here's a direct link to the website.

To be honest, most of the specs are pretty much what you'd expect to see on this calibre of PSU. There's support for all the latest motherboard standards, sleeved cables, support for multiple GPU's and a variety of safety features. The only thing that seems to be missing is information on what temperature the P8 1000w is capable of holding its full load at. I certainly hope its higher than 25c as mentioned in the MTBF specs, because we're going to be roasting it at double that today.

Be Quiet Dark Power Pro P8 1000W
DC Output+3.3V +5V +12V1 +12V2+12V3+12V4+12V5+12V6-12V+5VSB
Max Power 180W960W6W20W


The configuration of the +12v rails is rather odd looking with three of the rails being capped at 32A, two capped at 20A and one at 25A. Based on this, I can only assume that the GPU power is taken from the +12v4, +12v5 & 12v6, with the motherboard power coming from +12v1 and everything else from +12v2 and +12v3. However, as the P8 has the ability to combine (read:disable individual OCP) its rails into a single +12v rail, in the interest of simplicity this is how the unit will be tested today.

Onwards and upwards...

Be Quiet Dark Power Pro P8 1000w Review Page: 2

Be Quiet P8 1000w   ATX PSU



Let's not beat about the bush. The Dark Power Pro P8 comes in a bloody large box that looks more disproportionate to the size of the PSU than a midget driving a Land Rover. However, over-sized packaging is certainly nothing new with many manufacturers using it as a way to make buyers feel like they've got more for their money, and to be honest If I was to fork out a handful of notes on a new PSU I'd want it to come in something more substantial than a small brown recycled cardboard box.

Be Quiet Dark  Power Pro P8 1000w Box  Be Quiet Dark  Power Pro P8 1000w Box

At the front of the box Be Quiet! have kept things rather simple with a oscilloscope/heartbeat spanning the length of the box (I hope that's not a snapshot of the PSU's ripple output!!) and a light brown stripe down the side that contains the product name and power output details. Round the back we get a list of all the PSU's features in English and German along with a cable layout diagram, power distribution chart and lots of media awards....but AHEM, no Overclock3D's ones. tut tut tut!.

Be Quiet Dark  Power Pro P8 1000w Box Open  Be Quiet Dark  Power Pro P8 1000w Contents

Lifting the lid we can see why this box is so damn huge. Be Quiet has separated all of the accessories and modular cables into three cardboard boxes and positioned them around the outsides of the main box in a way that will protect the PSU sandwiched in the middle. Additionally the PSU has also been encased in a medium thickness layer of styrofoam ensuring that there is absolutely no way on earth that a courier could cause damage to the unit short of running it over with a 12 wheeler.

Be Quiet Dark Power Pro P8 1000w Accessories  Be Quiet Dark Power Pro P8 1000w Cables

Emptying contents of the various boxes reveals several unusual accessories, the most intriguing of which being a PCI slot cover fitted with a switch. While this may look like somebody accidentally slipped part of a cathode lighting kit inside the box, this switch can actually be used to alter the Dark Power Pro's +12v rail configuration from multiple rails to a single rail. However, should you not want a switch taking up a PCI slot at the back of your case, a small plug with a looped piece of wire has also been included to achieve the same effect.

As for the more ordinary accessories, you get a collection of cable ties (both velcro and plastic), some case screws, a power cord and a mass of modular cables that we'll cover in more detail on the next page.



On to the appearance now, and at first glance you'll be forgiven for labelling the P8 as 'just another black box'. Interestingly though, Be Quiet! have opted to construct the outer casing of their latest PSU from plastic. Now normally my first response would be to go "eugh....tacky" and take a few steps back, but in Be Quiet's defence the plastic is actually very rigid and almost indistinguishable in appearance to a painted metal box.

Be Quiet Dark Power Pro P8 1000w Review  Be Quiet Dark Power Pro P8 1000w Review

One of the advantages to using plastic is that you can pretty much design the outer casing however you like. Plastic is a lot easier to work with, and makes it easier for manufacturers to bridge the gap between form and function. This is exactly what Be Quiet! have managed to do with the Dark Power Pro P8's fan grill. Employing a low air resistance design, while also making it one of the focal points in the PSU's appearance.

Be Quiet Dark Power Pro P8 1000w Review  Be Quiet Dark Power Pro P8 1000w Review

For the most part, the rest of the PSU is fairly normal. There's a large specification sticker spanning one side of the unit, the top of the unit has some ugly bar-code stickers and round the front we have the usual honeycomb mesh fan grill along with a standard kettle lead socket and power switch. Due to the use of the plastic casing the grill is actually inset slightly meaning that slightly longer screws are required to attach the PSU to a PC case.

Be Quiet Dark Power Pro P8 1000w Rear  Be Quiet Dark Power Pro P8 1000w Rear Cable

As I've come to expect from BE Quiet, the back of the PSU is awash with modular connector plugs. Not only do you get the usual SATA/Molex and PCI-E ones, but there's also a total of four fan connectors should you not want to waste other valuable modular cables for simply hooking up your case fans. Another interesting feature is the pivoted surround on the main ATX cable outlet that protects the cable from damage due to over-bending.

Now the basics are covered let's move on to the next page.

Be Quiet Dark Power Pro P8 1000w Review Page: 3

Be Quiet P8 1000w       ATX PSU


Cables & Connectors

As with the previous Dark Power Pro P7 series, Be Quiet! have stuck largely to a PCI-e style connector interface. The only minor difference in the case of the P8 is that most of the connectors clip together at the sides rather than at the top. This prevents any potential issues where a cable being stretched to the side may lift the edge of the plug, partially loosing connection with the first few pins. As I've already mentioned, the 1000w model is fitted with a total of 14 connectors. Five of these are dedicated to SATA/Molex connectors, three are for PCI-e graphics card power, two are for P4/EPS motherboard power and the remaining four are for powering case fans.

Be Quiet Dark    Power Pro P8 1000w Modular  Be Quiet Dark   Power Pro P8 1000w Plugged In

Much like the Enermax MODU87+ I reviewed recently, the Dark Power Pro P8 also uses a 12-Pin connector layout for PCI-e graphics card power. The only issue with this is that it is often quite hard to get the plug on the end of the modular cable to mate with the connector due to the sheer number of pins that must align correctly inside. This was particularly apparent during the testing stages, where excessive force, manoeuvring and swearing was required to get the cables properly clipped into position.

Be Quiet! Dark Power Pro P8 1000w Connectors
 ATX ConnectorHard Wired
1x 20+4 Pin
 EPS-12v / P4-12v Connector(s)Hard Wired
2x 4+4 Pin, 1x 8 Pin, 1x 4 Pin
 Molex ConnectorsModular8x
 Floppy Disk ConnectorsModular2x
 SATA ConnectorsModular11x
 PCI-E ConnectorsModular3x 6+2 Pin, 3x 8 Pin

A decent amount of connectors are provided, but I really can't understand why manufacturers think it necessary to include so many SATA connectors. Seriously, does anybody really have eleven SATA Hard disks or DVD-RW drives in their PC's? I think not. Give us some more Molex connectors instead any day of the week.

Be Quiet Dark   Power Pro P8 1000w ATX  Be Quiet Dark   Power Pro P8 1000w EPS

Be Quiet Dark     Power Pro P8 1000w PCI-e  Be Quiet Dark  Power Pro P8 1000w Cables

The Dark Power Pro P8 pretty much has backward (and forward) compatibility nailed, with support for both P4-12v (4 pin), EPS-12v (8 Pin) and dual EPS-12v standards along with a 20+4 pin ATX connector. On the PCI-e connector front three of the six connectors are interchangeable between 6 and 8 pin standards ensuring support for dual and triple graphics card configurations.

Be Quiet Dark   Power Pro P8 1000w Short

It would also seem that Be Quiet! have also been listening to the needs of 'neat freak' enthusiasts by providing a small collection of short, single plugged Molex and SATA connectors. This avoids those situations where you're forced to use one of those 6ft long modular cable with multiple connectors sprouting out of it everywhere, when all you needed was to power the DVD-RW drive situated a couple of centimetres away from the PSU.



Lifting off the lid we get our first look at the internals. More importantly though, we get to see that the internal chassis of the Dark Power Pro P8 is made from steel. Hopefully this will help to settle the nerves of anybody who thought that Be Quiet! were silly enough to make the entire PSU from plastic.

Be Quiet Dark Power Pro P8 1000w Open  Be Quiet Dark Power Pro P8 1000w Metal

Be Quiet Dark Power Pro P8 1000w Fan  Be Quiet Dark Power Pro P8 1000w Fan

Rather than opting for a budget 3rd party fan to cool the PSU, Be Quiet! have gone with one of their very own Silent Wings USC models. Despite 'only' being a 120mm model as opposed to the 135mm fans using in various other PSU's, it still manages to put out a reasonable 50.32CFM at 17dBa (according to sources!).

Be Quiet Dark Power Pro P8 1000w Internals  Be Quiet Dark Power Pro P8 1000w Transformer

The internals are fairly tightly packed with three black aluminium heatsinks spanning the length of the unit. Two large transformers sit in the middle, and considering there are no VRM's anywhere to be seen, I'd hazard a guess that one of these provides the juice for the +12v rails while the other deals with the +3.3v and +5v outputs. A little bit more over to the right we can also see the ickle little +5vSB transformer that deals exclusively with +5v output when the PSU is in stand-by mode.

Be Quiet Dark Power Pro P8 1000w Primary Caps  Be Quiet Dark Power Pro P8 1000w Secondaries

Be Quiet Dark Power Pro P8 1000w Secondaries  Be Quiet Dark Power Pro P8 1000w Solid State

Capacitors are plentiful inside the P8, with a couple of Teapo 420v / 470uF / 85°C jobbies being used over on the primary (high voltage) side of the unit. Swinging round to the secondary side I can just about see some CapXon electrolytic caps mixed in with a handful of unidentifiable solid state ones. All in all, a bit of a mix-and-match affair.

Be Quiet Dark Power Pro P8 1000w Pots  Be Quiet Dark Power Pro P8 1000w Filter

If you're mad enough to stick your screwdriver in a powered on PSU *raises hand* there are also a selection of adjustable pots situated over on the secondary side (left pic) for fine tuning the voltage outputs of the unit. Of course, this can only be done reliably while the unit is powered on and under load, so be sure to wear rubber shoes (no, seriously...don't try it). Oh, and the picture on the right shows the input filtering, that isn't anything to shout about - but should still keep the nasties out.

Now to take her for a spin...

Be Quiet Dark Power Pro P8 1000w Review Page: 4

Be Quiet P8 1000w        ATX PSU

Today I'm going to be conducting the testing of the Be Quiet! P8 1000w on OC3D's trusty SunMoon SM-268+ DC load tester. This equipment is capable of placing a user specified load on all of the PSU's rails (+3.3v, +5v, +12v, -12v, +5vSB) up to a maximum load of 1680w.  As the maximum load for this device on the +12v rail is restricted to 75A I will also be bringing in our Analogic Series 2000 DC load tester for the 'MAX Load' stage of the testing, so that anything up to an additional 166A can be added if necessary.

As with all of Overclock3D's PSU testing conducted in the past year, all testing of the Be Quiet! Dark Power Pro P8 1000w will be conducted at Sahara-like temperatures of 50°C (±5%) with all results being recorded using a Fluke Digital Multimeter and Thermometer.

Ok, before we get down to discussing the results. Let's get familiar with the graphs. To start with, the highest and lowest values on the Y-axis (voltage) represent the maximum and minimum voltages allowed by ATX specifications. If a line goes off the graph then you can pretty much forget buying it. Luckily the Dark Power Pro maintains reasonable voltage stability throughout, staying extremely close to the ideal voltage (white line) on the +5v and +12v rails while in a 'normal' usage scenario on the green area of the charts.

The orange area indicates cross-load tests, in which the load placed on the PSU is heavily unbalanced (for example an ION based PC running two GTX480's). Of course, this is highly unlikely to be encountered in the real world but once again the Be Quiet has no problems at all dealing with the wonky loads and puts out some rather admirable voltages.

Finally the red area indicates our 'Max Load' test where the PSU is pushed to its absolute limits that are often well outside specifications. In the case of the P8 this was a whopping 1276w - not far off 300w more than the spec on its label. Here the +3.3v rail took a bit of a nosedive down to 3.2v, but the rest of the rails remained very close to their ideas, showing that the unit has some serious grunt.

The efficiency of modern PSU's also plays a large part in many peoples purchase decisions in recent times, and as we already know from the specs back on the introduction page, the P8 is stated as being 80PLUS Silver certified. This means that we should be seeing efficiency levels of at least 85% at 250w and 1000w loads, and 88% at 500w. And do we? YES. The P8 sticks to around 90% efficiency throughout all of the most important tests, only dipping into the 80's during one of the cross-load and max load tests. Of course these tests are not part of the 80PLUS certification procedure, so the unit easily meets its silver certification.

Now let's move on to the next page where you can get a look at the tabulated data along with temperature readings and ripple results...

Be Quiet Dark Power Pro P8 1000w Review Page: 5

Be Quiet P8 1000w         ATX PSU

OK, so we've seen the graphs over on the previous page. Now here's the data that they were derived from.

Be Quiet! P8 1000w Load Results @ 50°C
   +3.3v  +5.0v  +12v  +5vSB  -12v  AC Watts /
 DC Watts
 Efficiency  Intake /
Δ Temp
5.50A 5.50A 16.75A 1.00A  0.12A 282w /
90.42% 50.5°C /
3.33v 5.07v 12.06v 5.02v  -11.85v
11.00A 11.00A 33.50A 2.00A  0.25A  350w /
91.86%  50.1°C /
3.28v 5.04v 12.00v 4.94v  -11.90v
16.50A 16.50A 50.25A 3.00A  0.37A 835w /
 90.77% 51.0C /
3.24v 5.01v 11.94v 4.86v -11.99v
22.00A 22.00A 67.00A 4.00A 0.50A 1124w /
89.14%  49.8°C /
3.21v 4.98v 11.86v 4.80v -12.02v
22.00A 22.00A 1.00A 0.00A 0.00A 239w /
81.17% 49.5°C /
3.27v 5.04v 12.04v 5.09v -12.32v
 1.00A  1.00A  67.00A  0.00A  0.00A 884w /
91.62%  50.8°C /
3.30v 5.04v 11.96v 5.08v -12.53v
 30.00A 30.00A 85.00A 4.00A 0.50A 1486w /
85.86% 48.5°C /
3.20v 4.96v 11.86v 4.77v -0.11v

To reiterate what's already been said over on the previous page, the Dark Power Pro P8 shows excellent voltage stability on the +12v and +5v rails across all loads including the cross-load and max load tests. The +3.3v rail is the only area where the unit is let down a little, but even then the voltages still remain fairly acceptable and well inside ATX specifications.

Another thing I've already mentioned is the results from the 'Max Load' test where the PSU showed that it was capable of holding 1276w continuous. Not only that, but if you look at the load on the +12v rail it held a massive 85A load - plenty enough for any kind of crazy over the top multi-GPU configuration.

Efficiency was also above expectations with the unit sticking to around 90% efficiency through Tests 1-4. Only in the first cross-load test did it drop down to 81%, but this is quite common for most PSU's when a heavy load is placed on the +3.3v & +5v rails with little on the +12v rails

Be Quiet! P8 1000w Scope Results @ 50c
   +3.3v  +5.0v  +12v
Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review
Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review
Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review
Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review
Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark   Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review
Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review
Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review Be Quiet Dark  Power Pro P8 1000w Review

EEK! No I didn't mix up the results from the +12v rail with those from a Seismograph in the middle of an earthquake! But yes, the ripple on the +12v rail is less than ideal with the results climing from 50mV in Test 1 to a maximum of 136mV in Test 4. Considering that ATX specifications state that ripple on this rail should be no more than 120mV it looks like Be Quiet have some work to do here. Of course, these levels aren't exactly dangerous - for example I've seen other well known brands hit over 250mV, but there are still plenty of other brands on the market that do a much better job.

The +3.3v and +5v rails on the other hand were quite acceptable, with the closest call being the +3.3v rail in Test 4 that came within 8mV of ATX's recommended 50mV limit.

Now let's try and form some kind of conclusion...           

Be Quiet Dark Power Pro P8 1000w Review Page: 6

Be Quiet P8 1000w          ATX PSU

I think it's fair to say that the review of Be Quiet! latest PSU has been quite a roller-coaster ride today. To start with, the use of plastic casing on the outside of the PSU came as quite a shock. However, when you consider that this not only helps to dampen noise, insulate against heat escaping into your PC case and prevent the PSU looking like it's got a few rounds with Freddy Krueger after it has been swapped between a few systems, it actually becomes quite an innovative idea.

Performance-wise, the P8 delivered exceptional voltage stability on the +5v and +12v rails, with the +3.3v rail only letting the team down a little by dropping to 3.21v when the unit was running at 1000w load. The cross-load results proved to be excellent with the PSU not being fazed in the slightest by the unusually uneven loads that were thrown at it. In the max load test the unit managed to run continuously at 1276w with only minor differences in the voltage output to the 1000w load results.

Efficiency and temperature results were also above expectations and allowed the unit to keep the speed of it's 120mm fan at a minimum resulting in extremely quiet operation. At last, a product that lives up to its name!

Unfortunately the biggest negative point for me was the ripple output on the +12v rail. Don't get me wrong, because by no means is it 'terrible' or a total deal breaker. But with 136mV ripple at full load (16mV above ATX recommendations), it wouldn't have taken Be Quiet much at all to bring it down to more reasonable levels with a little bit of extra filtering. Then this PSU could have potentially a gold award winner.


The Good
- Very stable +5v and +12v output.
- Efficiency exceeds 80PLUS Silver requirements.
- Silent....very silent.
- Plastic outer-casing has several advantages.
- Usual mass of modular connectors expected from Be Quiet.
- Managed to hold close to 1300w load.
- Ability to switch between single & multiple +12v rails (if you feel the need to!)

The Mediocre
- 3.3v rail not quite as stable as the others.
- 12-Pin Modular connectors not the easiest to insert.

The Bad
- Not exactly 'bad', but worse than mediocre - the +12v ripple results.



Thanks to Be Quiet for providing the P8 1000w for review. Discuss in our forums.