Introduction

be quiet! has built a solid reputation for itself in the PSU market, and it's undoubtedly looking to continue this tradition with the latest iteration of the Straight Power family. This new Straight Power 12 power supply benefits from the 80+ Platinum certification. The design does not change a bit with a grid that characterizes this series. The be quiet! Straight Power 12 series power supply offers a wire-free design. There are no internal cables (on the DC side), and all connections are only run through the PCB. This design allows for non-obstructed airflow, which should, theoretically, increase cooling performance. This wire-free design will also allow for better signal quality and less signal disturbance, and these factors should increase component lifespan. Last but not least, the 1200W unit feature two 12VHPWR connectors.



The Straight Power 12 is available in six capacities – 750W, 850W, 1000W, 1200W and 1500W to cover a broad range of systems and budgets. The electronics in the unit uses Japanese brand capacitors. The Straight Power 12 1200W is designed with OVP/OPP/SCP/UVP/OCP/OTP current and voltage protection.





Packaging & Contents

The packaging for the Straight Power 12 Platinum is standard for be quiet!. They carry a similar design ID to what we have seen on their cases. They include plus marks with the features integrated into the unit. I do like that the iconography is minimal, and be quiet! in standard fashion keeps things relatively simple. At the top and left we have the logo of the 80+ Platinum certification, while in the right corner takes place the logo of the brand.



On the back, in addition to a few lines evoking the be quiet! brand, we have a table mentioning the electrical characteristics of our Straight Power 12 1200 W.
The brand adds the mention “Developed in Germany”, but the fact remains that the power supply is made in China. Another mention highlights one of the specificities of the ATX 3.0 standard, which is compatibility with PCIe 5.0.



On the edges we can see the logo of the brand, the name of the product as well as the power of the unit.



Opening the package and sitting at the top of power supply is the multi-page booklet style manual.




The manual is a multi-page booklet, and it helps to explain the PSU capabilities and features for the entire Straight Power 12 Platinum lineup. This book may look rather large, but keep in mind that the data applies to six total PSUs.



The power supply is wrapped in a bubble wrap bag, and the cables are in two bundles under the cardboard flaps on each side of the supply.



The accessory pack includes cables, some black cable ties, a power cord and five black screws (the extra one is a spare). A large number of cables accompanies the PSU including two EPS, four PCIe options plus two PCIe 5.0 cables. This is expected, of course, given the huge capacity.



You can see the cable types and lengths in the image below – the selection is sensible and more than adequate for high-end builds.



All cables are long enough, but I would like to see an even longer ATX cable of 650 mm or more. The peripheral connectors are adequately far apart at 150 mm.



All the cables are fully sleeved, which looks neat but does add to the bulk – again, though, most larger cases should accommodate everything easily enough.





A Closer Look Outside

Power supplies are rarely exciting visually, and the Straight Power 12 plays it safe with its smart all-black design. Importantly, it feels very well made and is up to be quiet!'s usual standards in this regard. Our 1200W model is 180mm deep, which is about what you'd expect. It does make it better suited to larger cases, but given that the capacity is so high this isn't likely to be a problem. 1200W is well suited to high-end, multi-GPU systems and workstations. Here we have the input side of the supply, and it is where we find the main AC input receptacle. Also, here is the mains toggle with eth decal above noting it can support from 110-240Vac input. Unlike several we have seen, be quiet! opted to make the area around the AC input and the mains toggle to be solid, while others open these areas up with mesh venting to allow airflow for cooling the PSU.



We take a look at the grille. Just like in its 11 version, the Straight Power 12 keeps the ventilation which comes in the form of a 135 mm Silent Wings, its 6-pole motor and its FDB type bearing (Fluid Dynamic Bearing ). Also the very artisan look with bars running the length of the supply's fan opening to protect the fan itself from accidental intrusion remained. The metal bars feel very reminiscent of an art piece or maybe headers on a supercar. I know I'm getting lost in the weeds for a PSU fan grille, but I do feel like it is truly a well-made and well-integrated piece. The Straight Power 1200W features a modular cable design that allows you to use only the cables required for your system. The full modularity gives you maximum control over what cables are connected and where they're connected, which will help you out in your cable routing efforts. Unlike on other be quiet! power supplies the Straight Power 12 doesn’t feature the OC key or fan headers. Truth be told nobody needs fan control at the PSU level and only a select few hardware enthusiasts would benefit from the OC Key which binds the 12v rail into a single mono block. Here we have a peek at the modular output connectors for the Straight Power 12 Platinum, and I like how this is arranged. We can see a 20+4 pin ATX, two 8 pin EPS (P4+P4 and P8), two PCIe 5.0 12VHPWR, four 6+2 pin PCIe, nine SATA and two Molex.



Here we see the section opposing the fan, which is where we would generally see the main label. This area is now a blank slate, which may be favorable for a system without a PSU shroud in place as it is solid black. I still do have mixed feelings on this and feel that for aesthetic purposes, the top bale is better than the side as that is what you will see for the most part through a window side panel.



On one side we find a power label: you’d see this if you mount it with the fan facing down in the bottom of your case.



Here we have the other thin side, which is opposite the label side. This is the indented be quiet! logo. I do like this aesthetic as it is subdued enough not to be considered pretentious, but it still shows your branding.




A Closer Look Inside

This Straight Power 12 Platinum 1200W PSU review won’t be complete if we don’t look into the product’s interior. By dismantling the power supply, we are doing away with the 10-year guarantee. Indeed, the seal crumbles as soon as we start to peel it off. The fan is a be quiet! Silent Wings 3 model at 135mm. It is a 6-pole FDB fan with a maximum RPM of 2600RPM.



The Straight Power 12 Platinum 1200W model is characterized by the use of a full bridge, which is complemented by LLC resonant conversion, synchronous rectification and independent DC-DC converters for 5V and 3.3V lines. We assigned the EMI filter to the first zone, which is divided into two parts - one on a small separate board, and the second on the main board. It includes four Y-capacitors, two X-capacitors, two choke coils and a varistor.



The second zone contains a diode assembly with an independent heatsink, two high-voltage Nippon Chemi-Con capacitors (420V, 470uF, 105°C each or 940uF combined) along with a 3rd 420V Nippon Chemi-Con capacitor and (420V, 330uF, 105°C), all 105º. Τheir combined capacity looks to be enough to cover the needs of this PSU.




Instrumentation used


Sleek and stylish. The be quiet! Straight Power 1200W looks to be a fantastic design both internally and externally. There is though, and of course, the small matter of how this actually performs when operating. So, without further a do, let’s get this strapped onto our test bench and see how it does!Below we report the instrumentation used in the test phase for the Straight Power 1200W.



PowerKiller 2.0. Test bench designed for power supplies up to 2185W.
Stingray DS1M12 USB Oscilloscope
PCE-PA 6000 Wattmeter
Range 1W ~ 6kW
Accuracy ± 1.5%
Multimeters
3 x HT81
1 x ABB Metrawatt M2004
1 x Eldes ELD9102
1 x Kyoritsu Kew Model 2001
1 x EDI T053
Multi-Channel Datalogging Digital Thermometer PCE-T 1200
Center 325 sound level meter


Voltage Regulation

Voltage regulation tests are performed by connecting all power lines to our PowerKiller simulating the behavior of the power supply with loads comparable to those of a real location.

Line +3,3V



Average voltage 3.308 volts
Deviation from the ideal value (3.33 volts) = -0.66%

Line +5V



Average voltage 5.018 volts
Deviation from ideal value (5.0 volts) = +0.36%

Line +12V



Average voltage 12.130 volts
Deviation from the ideal value (12.0 volts) = +1.08%

This test confirms the robustness of the electronics used. The voltages on the three lines of interest maintain an average value very close to the reference one without the need for increased no-load voltages. The voltage drop is extremely limited if we consider the high power range, a sign that the supplied wiring and the internal conductors of the power supply have been wisely sized.


Efficiency

At the point of maximum efficiency, the Straight Power 12 1200W is able to deliver 600W wasting just 35W.




Ripple

3.3 volt @ 100%



5 volt @ 100%



12 volt @ 100%



Less than 20 mV on both the 3.3 and 5 volt rails is excellent while less than 40 mV of ripple on the 12 volt rail is similarly impressive.


Cross Load

Line +3,3V





Maximum Vdrop 0,04 volt (1,19%)

Line +5V





Maximum Vdrop 0,04 volt (0,79%)

Line +12V





Maximum Vdrop 0,18 volt (1,47%)

This test session, aims to establish the robustness of the individual lines, shows respectable results. The excellence threshold set at 2% is widely exceeded, a sign that this power supply has been designed to deliver the rated currents in absolute tranquillity.


APFC

The power factor control system (APFC) manages to tick the almost absence of phase shift already at 75% of the maximum load. The trend is respectable and in line with that obtained by the best high-end power supplies.



Overload



Even in conditions of heavy overload the voltages are excellent, as is the efficiency of just over 90%, with a power absorbed by the mains of 1835W (the Straight Power 12 1200W display shows slightly higher values than our instrumentation). We are really dealing with an extreme power supply, so "strengthened" as to be able to deliver more than 1600W without problems and for several minutes. During our tests we have ascertained that the protection system also allows peaks of over 1700W to run with an absorption from the electricity grid of about 2kW! Obviously, if the power surplus is requested suddenly or for an excessive duration, the power supply will be switched off by the control electronics, which is why we can confirm that the overload protection is present, but it turned out to be a titanic undertaking to be able to do it also intervene for our test bench. Difficult, if not impossible, therefore, that a real location could embarrass this authentic marvel.

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Temperature

The large FDB fan and high efficiency of the design ensure that the temperatures are always well maintained inside the chassis, even under high load situations.




Noise

The acoustic impact test, aimed at defining the noise values that the power supply generates during its operation, is the only test that we are usually forced to "simulate". In fact, our test bench requires adequate cooling in order to be able to absorb hundreds of watts of power, which does not go well with the need to eliminate any external source of noise in order to be able to evaluate the one produced exclusively by the power supply. For this reason, the test is usually conducted by powering the fan externally and simulating the rotation speeds at the load, if indicated by the manufacturer, or simply the noise level over the fan's operating range if the association is not available. We remind you that the value perceived by our hearing as close to silence is 30dB and that increments of 10dB correspond to a perception of doubling of the noise level. The correspondences of these values are easily observable on the noise scales available on the net. Ambient noise 29.2 dBA.



As we had already anticipated in the previous pages, the be quiet! Straight Power 12 1200W uses a fan that is as performing as it is versatile, in fact managing to reconcile a high air flow rate, guaranteed by the generous dimensions and a maximum rotation speed of 2600 RPM, with a extremely silent at low load. In a well-ventilated case with realistic loads, the Straight Power 12 1200W will hardly make itself felt!


Final Thoughts

First impressions are positive, the textured finish feels great in the hand, and it proves to be very resilient to scratches and is basically immune to messy looking fingerprints. The grille alone is something that is simply put, beautiful, and while, for most, it will be hidden forever, it creates a special feeling when you first open it up and see it. It is always reassuring to see 105c rated Japanese capacitors used in a design, and be quiet! have not cut any corners in the design of this unit. It uses high grade Japanese electrolytic caps in both primary and secondary stages. To top things off the Straight Power 12 Platinum’s fully modular design, excellent array of connectors, high quality cabling and 10 year warranty make it an excellent choice for a high end multi-GPU or multi-CPU systems. Technically it didn't disappoint either, delivering stable power across a wide range of power demand situations. It also handled our challenging cross load tests without a hitch. The overall efficiency of the unit is high, hitting a peak over 94% during a load demand around 55%. It managed to deliver 1600W Watts before safely shutting down, and it maintained a sustained 1700 Watts load for quite some time in my testing, showing that it is clearly over specced, giving headroom under heavy load situations. The ripple suppression was also top-draw and will ensure that your components remain stable, especially when overclocking, and prolong their lifespan with clean power delivery.



The Straight Power 12 Platinum 1200W is a great option for building a high performance multi-GPU gaming or work system. This model combines a first-class component base and a rich set of cables for connecting various devices, and is also characterized by a low noise level, which depends on the load. If you load it to the maximum, the fan became clearly audible, but the sound was monotonous and not irritable (and was lost against the background of noise from other system components). And the internal components, at the same time, warmed up by no more than 65 degrees. But the important thing is that the power supply has the highest stability and excellent efficiency. In addition, if you are not a fan of any RGB LEDs and similar system modding, then the strict and modern appearance of Straight Power 12 Platinum will definitely appeal to you. The Straight Power 12 1200W power supply is currently available for 215€. At this price it really would be our first choice and offers up the benefits of a 1200W, quality PSU to a wider audience. Admittedly though, the key highlight when it comes to practicality is undoubtedly seen in its support for PCIe Gen5 and ATX 3.0.