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be quiet! Dark Power Pro 11 850W Power Supply Review

Our Verdict

A high-performance PSU that is the most silent unit we have ever tested (passive PSUs excluded). FSP's cooperation with be quiet! has delivered an excellent product that will please all noise haters.


  • • Full power at 46°C • Performance • Japanese caps • Silence • FDB fan • OCK feature • External Fan control • Lots of connectors


  • • Price • 5VSB efficiency • No stealth or flat cables


You might have guessed that be quiet!’s mission is to offer products that output the lowest possible noise, even under tough conditions. The company has a long history of making PSUs, and its products are popular in Europe, especially among German users who prefer hardware that operates silently. be quiet! also offers silent cooling solutions, and recently entered the PC case market.

Until now, the Dark Power Pro 10 series comprised be quiet!’s flagship PSUs, but the competition continues to improve, especially at the high end. The new series lists three models with capacities ranging from 850 to 1200W. be quiet! tells us it will have three mid-capacity models (in the 550 to 750W range) in August. Interestingly, with this series, be quiet! returns to FSP, rather than Seasonic, for manufacturing.

We put the 850W model to the test. It is equipped with a 135mm SilentWings 3 fan developed exclusively for use in PSUs, which is worth mentioning because most PSUs use general-purpose fans, some of which aren’t well suited for the purpose. For example, the popular sleeve-bearing fans that we find in most affordable PSUs aren’t suitable for horizontal mounting, and their lifetime is greatly reduced inside of PSUs where they're usually mounted horizontally.

The Dark Power Pro PSUs feature an overclocking key, carried over from the previous generation. This key is actually a simple switch (or a jumper) that converts the PSU from a multi-+12V rail unit, as it comes from the factory, to one with a single +12V rail. This feature eliminates any problems that may arise from triggering overcurrent protection (OCP) once you begin overclocking power-hungry graphics cards. In most cases, GPUs and CPUs consume power voraciously under extreme overclocks, which is why most professional overclockers use high-output PSUs.


Efficiency in the Dark Power Pro 11 is 80 PLUS Platinum-rated, and the unit is Haswell-ready since it has DC-DC converters for generating the minor rails. It can deliver its full power continuously at an ambient temperature of up to 50 degrees Celsius (122 degrees Fahrenheit). The list of protection features is complete, including over temperature protection (OTP) and a high-quality FDB fan that will operate for 300,000 hours, according to be quiet!. The lack of a semi-passive mode isn’t a problem, since the fan operates at low speeds under light loads, preventing internal heat from building up.

One downside, however, is that the PSU is quite long, at a little more than 19 centimeters (7.4 inches). And although the warranty is satisfactory, we would like it to be even longer, given the unit's price.

Power Specifications

Max. PowerAmps25253030353530.5
Total Max. Power (W)850

This is one of the few PSUs with multiple +12V rails to enter our lab lately. However, be quiet! provides the option to convert them to a single +12V rail with the flip of a switch or through a jumper wire. The minor rails are pretty strong (140W combined), while the 5VSB rail has 0.5A more current than typical mainstream PSUs.

Power Distribution

Power Distribution
12V1ATX, Peripheral, SATA
12V2EPS1, EPS2
12V3PCIe1, PCIe2
12V4PCIe3, PCIe4

Power distribution on this unit is optimal, since the EPS connectors are fed from a dedicated rail and don’t get mixed up with the PCIe ones. Below, you will find the modular board's rear panel, which shows the EPS and PCIe numbers that we list in the table above.

Cables And Connectors

Native Cables 
ATX connector (610mm)20+4 pin
Modular Cables 
4+4 pin EPS12V/ATX12V (700mm)1
Eight-pin EPS12V (700mm)1
6+2 pin PCIe (600mm)6
Six-pin PCIe (600mm)1
SATA (600mm+150mm+150mm)6
SATA (600mm+150mm) / four-pin Molex (+150mm+150mm) / FDD (+150mm)2 / 2 / 1
Four-pin Molex (600mm+150mm+150mm)3
Four-pin Molex (600mm+150mm) / FDD(+150mm)2 / 1
Four-pin Molex - MB connector (600mm)1
Four-pin Molex for Fan (600mm) / External Fan Connector (+160mm)4  / 4
Overclocking Key (700mm)1

There are a lot of PCIe and EPS cables, given this unit's capacity. We usually see this many connectors in 1kW PSUs. The EPS and PCIe connectors are available at the same time, meaning that, theoretically, this PSU could support three video cards and a high-end motherboard. The single, six-pin PCIe and four-pin Molex connectors are for motherboards that support them, in areas where more power is needed. In addition to all of the typical PSU connectors, we find four connectors for external fans and another that connects the PSU with the overclocking key bracket. Finally, all of the PCIe and EPS connectors use thicker AWG16 wires, and the +12V wires on the 24-pin ATX connector have the same diameter. The rest of the wires are AWG18, which is recommended by the ATX specifications.

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