Introduction

We would like to thank be quiet! for supplying the review sample.

Popular German brand be quiet! has a new flagship PSU line, the Dark Power Pro 12 consisting of only two members with capacities of 1200 W and 1500 W. Both use a platform provided by Channel Well Technology (CWT) and are 80 PLUS Titanium certified. The 1500 W model has also been certified by Cybenetics, as ETA-A+ in efficiency and LAMBDA-A- in noise output with 115 V input. With 230 V, it doesn't manage the ETA-A+ efficiency and drops to ETA-A.

Both Dark Power Pro 12 units are fully modular and have several +12 V rails, which can all be combined through an "overclocking key"—basically a jumper. Another notable feature is the frameless fan, which allows for higher airflow and lower noise. Lastly, at ten years, the provided warranty is long compared to most competing offerings—only Seasonic provides longer warranties with its Prime models.

The Dark Power Pro 12 with 1500 W maximum power output is suitable for workstations that include multiple graphics cards and power-hungry processors. Given the NVIDIA RTX 3090 can consume up to 400 W, you can use this PSU to power two of these cards along with an AMD Threadripper and have plenty of headroom left for your other devices. After all, it is not wise to fully utilize a PSU—10%–20% headroom should always be available, even for your worst-case scenario. You see, PSUs age as well, so performance under severe conditions won't stay the same as they do.

be quiet! marketing dubs this a digital platform, which is indeed the case for the APFC converter, primary switching FETs, and FETs that handle the +12 V rail. However, it is not a fully digital design as it doesn't allow you to monitor or control any of the PSU functions in software, which is the case for the Corsair AX1600i. Moreover, the platform doesn't use cutting-edge technology, so it cannot compete with the Corsair AX1600i, which utilizes GaN MODFETs in its bridgeless totem-pole PFC converter.

be quiet! let me know that these PSUs utilize fan-failure protection. An auto-restart function in the fan's circuit has it restart automatically if it fails to spin up. However, every PSU out there includes such a feature. They also mentioned that the fan has Over Temperature Protection (OTP), with another, similar protection circuit inside the PSU. That said, there is no actual fan-protection circuit since I removed the fan to shoot the IR images and the PSU was operating normally. With fan-failure protection, the PSU wouldn't even start with its fan disconnected. Someone could argue that OTP makes sure there won't be any problems with the fan removed, but fan-failure protection and OTP are two different protection features.


In its PR kit, be quiet! mentions that semi-digital PSUs only use an MCU for the APFC converter, while fully digital PSUs control the PFC, LLC, +12 V circuit, and protection features. I don't entirely agree on this as a fully digital PSU should have all of its significant circuits controlled by MCUs, including any protection features, the PFC, LLC, +12 V, DC-DC converters for the minor rails, and 5VSB circuit. Unfortunately, today's market does not include a fully digital PSU.

Specifications

The box is huge, which isn't surprising for such a large PSU.


Everything is neatly arranged into the box, and you get plenty of accessories, including Velcro straps, zip ties, a bunch of cable combs for the individually sleeved cables, and two sets of fixing bolts. There is the overclocking key, or keys, to be more precise, since there is also a plain jumper, which does the same job as the overclocking switch, but without the option to return to multiple rails. To do so, you have to access the PSU's rear panel and remove the jumper.


The exterior design is excellent and screams of high quality. At the face, the exhaust grill is restrictive, and the heavy-duty switch and C20 inlet show that this PSU means business.


You will find the specifications label on one side, while the other has a nice logo of the line.


At the rear, all sockets feature descriptions, and the virtual 12 V rails that feed them with power are also depicted to ensure the modular cables are connected correctly. In a multi-rail +12 V PSU, connecting all the cables correctly is vital as OCP may inadvertently trigger under high loads otherwise. You can avoid this issue altogether by enabling overclocking mode, where all virtual +12 V rails are merged into one by disabling OCP on this rail.


The fan grill is restrictive, which does help keep EMI under control.

Cables and Connectors

You get a ton of cables and connectors with the P12-PRO-1500, including two EPS and ten PCIe options. There are enough SATA connectors for even a data-storage server, and the 4-pin Molex connectors are more than enough as well. Two FDD adapters are also provided!


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. Finally, there are no in-cable caps, and the EPS and PCIe connectors use thicker 16AWG gauges.


According to be quiet! you should use socket A if two or fewer PCIe connectors are needed. This socket is linked to both the 12V5 and 12V6 rails, with the load equally distributed among these rails. If you want to use more PCIe connectors, start with sockets B and leave socket A for last.

Component Analysis

Before reading this page, we strongly suggest a look at this article, which will help you understand the insides of a PSU better.



This platform is by CWT and looks familiar because all semi-digital CWT platforms use the same controllers. Although the design is modern, it still does not compare to the cutting-edge technology used in Corsair's AX1600i, which is weird since the AX1600i is the main competitor of the P12-PRO-1500.


The transient filter is complete, and to save energy, it includes a discharge IC for the bleeding resistors of the X caps.


There is an NTC thermistor supported by a bypass relay for protection against large inrush currents. Moreover, an MOV handles surge voltages.


The two bridge rectifiers can handle up to 50 A of current.


The APFC converter is an interleaved design, which minimizes input/output current ripple and lowers conduction losses, thus increasing efficiency and doubling the effective switching frequency.


Two On Semiconductor NCP81071 ICs drive the PFC FETs.


The bulk caps have a combined capacity of 1830 uF.


Four Alpha & Omega AOTF29S50 FETs are the main switching FETs, and a pair of Silicon Labs Si8233BD driver ICs handle them.


One of the digital controllers handles the interleaved PFC converter and unit's protection features. The other MCU is responsible for the primary switching FETs, LLC resonant converter, and FETs regulating the +12 V rail. It also controls fan speed and some of the protection features.


Instead of a single large transformers, two parallel ones are used. This design offers higher efficiency since the load is equally distributed on the transformers.


Twelve On Semiconductor FETs generate the +12 V rail.


The DC-DC converters that generate the minor rails are controlled by an analog IC provided by Anpec. Moreover, six FETs in total are used by both converters.


Most electrolytic caps are of high quality. A large number of polymer caps are also used.


Besides the digital controllers, CWT used two Weltrend ICs for the PSU's protection features. The one installed on the modular board handles +12V OCP.


This daughter board hosts the circuit that generates the 5VSB circuit, which is also controlled by an analog IC.


Soldering quality is excellent.


To restrict ripple on all rails, several polymer caps have been installed on the modular board.


The frameless cooling fan is an interesting concept.

Test Setup