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Be Quiet! Dark Power Pro 11 1200W PSU Review

be quiet! says it's committed to building silent products, including the company's top PSU line, the Dark Power Pro 11. In this review, we will put the 1200 W Dark Power Pro 11 model to the test, which promises good performance and silent operation.

A Look Inside And Component Analysis

Parts Description

Our main tools for disassembling PSUs are a Thermaltronics soldering and rework station and a Hakko 808 desoldering gun.

Primary Side
Transient Filter4x Y caps, 2x X caps, 2x CM chokes, 1x MOV
Inrush ProtectionNTC Thermistor & Relay
Bridge Rectifier(s)2x Shindengen LL25XB60 (600V, 25A @ 113°C)
APFC MOSFETS3x STMicroelectronics STF31N65M5 (710V, 13.9A @ 100°C, 0.148 Ohm )
APFC Boost Diode2x CREE C3D06060A (600V, 6A @ 154°C)
Hold-up Cap(s)2x Nippon Chemi-Con (420V, 470uF each or 940uF combined, 2000h @ 105°C, KMQ)
Main Switchers4x STMicroelectronics STF26NM60N (600V, 12.6A @ 100°C, 0.165 Ohm)
Driver ICs (Main Switchers)2x Silicon Labs Si8233BD-C-IS
APFC ControllerInfineon ICE2PCS02
Switching ControllerChampion CM6901
TopologyPrimary side: Full-Bridge & LLC Resonant Converter Secondary side: Synchronous Rectification & DC-DC converters
Secondary Side
+12V MOSFETS8x Infineon BSC014N04LS (40V, 100A @ 100°C, 1.4 mOhm)
5V & 3.3VDC-DC Converters: 2x Infineon MOSFETs PWM Controller: APW7159
Filtering CapacitorsElectrolytics: Nippon Chemi-Con (105°C, KY, KZH), Rubycon (105°C, YXF) Polymers: Nippon Chemi-Con
Supervisor ICSITI PS223S (OVP, UVP, OCP, SCP, OTP )
Fan Modelbe quiet! SilentWings 3, SIW3-13525-HF (135mm, 12V, 0.56A, 84.60 CFM, 1800 RPM)
5VSB Circuit
Rectifier1x International Rectifier RFR1018E (60V, 56A @ 100 °C, 8.4 mOhm)
Standby PWM ControllerPower Integrations TNY279PN
-12V Circuit
PWM ControllerAPW7174
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Dismantling this PSU wasn't easy. Lots of screws had to be removed and we had to be extra careful not to break any of the clips of the rear plastic cover on the modular panel. In the primary side be quiet! used a full-bridge topology along with an LLC resonant converter, while in the secondary side a synchronous design was used, along with a couple of DC-DC converters that generate the minor rails. All components are of high quality, with the capacitors provided by Japanese manufacturers, so we expect them to be highly reliable.

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The first part of the EMI filter starts at the AC receptacle and includes a couple of Y capacitors. It continues on the main PCB with two more Y caps, two X caps, two CM chokes and an MOV. Finally, there is an NTC thermistor for protection against large inrush currents and an electromagnetic relay that allows for a fast cool-down.

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The two bridge rectifiers are provided by Shindengen (model number LL25XB60). Combined, they can handle up to 50 A of current, so they will easily meet the demands of this PSU.

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In the APFC converter we found three STMicroelectronics STF31N65M5 FETs along with a pair of CREE C3D06060A boost diodes. The bulk caps are from Nippon Chemi-Con (420V, 470uF each or 940uF each; 2000h at 105 degrees Celsius, KMQ series) and their capacity looks low for more than 16 ms of hold-up time.

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The APFC controller is an Infineon ICE2PCS02 IC, which is installed on the solder side of the main PCB. In the photo above, the ICE2PCS02 is in the middle, while the top IC is a SEN013DG, which is described as a "Zero Loss High Voltage Sense Signal Disconnect IC." Briefly, the SEN013DG disconnects the APFC converter while the PSU is in standby mode, in order to allow for the lowest possible energy consumption in this mode. Finally, the IC located in the bottom-left corner is an LM393, dual voltage comparator.

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The main switchers, four STMicroelectronics STP22NM60N, are arranged into a full-bridge topology and the switching controller is a Champion CM6901. On the same board as the CM6901 is a TS358CD operational amplifier (op-amp). The driver ICs of the main switching FETs are two Silicon Labs Si8233BD-C-IS, which support switching frequencies of up to 8 MHz. Finally, an LLC resonant converter boosts efficiency by restricting switching-energy losses.

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On the secondary side, eight Infineon BSC014N04LS FETs regulate the +12V rail. These are installed on the solder side of the main PCB. They are cooled down by the casing and two small heat sinks, which are installed on the component side of the PCB.

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Both DC-DC converters that generate the minor rails are installed on a vertical PCB located on the secondary side. The common PWM controller of both VRMs is an Anpec APW7159.

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All electrolytic capacitors on the secondary side are rated at 105 C (221 degrees Fahrenheit) and most of them are made by Nippon Chemi-Con, while the rest are made by Rubycon. Finally, all polymer capacitors are made by Chemi-Con. This is an excellent choice of caps; we expected nothing less in a high-end PSU that costs almost $280.

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The circuit that handles the regulation of the 5VSB rail is located on a separate daughterboard, upon which we identified an International Rectifier RFR1018E FET and a Power Integrations TNY279PN standby PWM controller.

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On the front side of the modular PCB, we found many filtering, polymer caps by Chemi-Con. On the back side of the same board, we would have liked a cleaner design.

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The PSU can control up to four external fans and this is accomplished with a separate sensor, which allows the fans to be electrically independent from the unit's internal fan.

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For the generation of the -12V rail, be quiet! used a dedicated circuit, which includes an APW7174 PWM controller. This is quite impressive since in most PSUs ─ even high-end ones ─ usually only a single diodehandles this task along with the suitable filtering components.

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Like in the Dark Power P11-850 unit that we evaluated a while ago, soldering quality isn't among the best we have seen. We would like to see better soldering, and on the component side of the main PCB, some components aren't properly aligned in place, showing that FSP's production needs some improvements. We also found some component leads that were quite long, and in some cases were too close to each other.

The cooling fan carries be quiet!'s logo and belongs to the SilentWings 3 family. Its model number is SIW3-13525-HF (135mm, 12V, 0.56A, 84.60 CFM, 1800 RPM), and since it uses a fluid dynamic bearing it is going to last for quite a long time. Overall, it has a silent operation due to its pairing with a highly relaxed fan profile.