be quiet! SFX L Power 600W

[testman78]

Introduction

The world of Small Form Factor (SFX) power supplies has been a fierce battleground over the last few years. Gaming systems have been getting smaller, the HTPC and Steambox markets are growing in popularity and the demand for a tiny PSU that can keep the system small, but still deliver the high-performance grunt required by modern gaming GPU/CPU combos is at an all time high. be quiet! is a key player in the PSU's, with several offerings in that category. Unfortunately, the form factor's shallow depth doesn't allow for fans larger than 80mm in diameter. And smaller fans mean more noise output, since they have to spin faster. Because acoustics are an important buying factor for many users nowadays, be quiet! tweaked the SFX form factor and introduced SFX-L, which has the same width and height as SFX, but specifies increased depth to allow for a larger cooling fan that's up to 120mm in diameter. Just how big are SFX L power supplies? The be quiet! SFX L Power 600W unit specifically measure 64 x 125 x 130mm. It also come conveniently with an ATX adapter so it can be readily used even inside non-SFX cases. It features a fully modular design, supporting Intel's Deep Power Down C6/C7 mode. Moreover, this SFX L unit meet Energy Star 6.0 guidelines and fulfills ErP guidelines. Despite the compact size, it supports up to four PCIe video card connectors for multi-GPU use.



The SFX L Power 600W PSU meets the 80 PLUS Gold requirements, which should allow for a more relaxed fan profile, since energy loss will be kept at low levels even under full-load conditions. Thus, the fan won't have to rotate at its maximum speed in order to dissipate heat. In the dimensions section, we see that the only difference between the SFX-L and SFX units is a 13cm depth measurement compared to 10cm, respectively. We all love tables right? This section has a couple of big ones, enjoy!



Here's the ratings on the DC rails:




Packaging & Contents

We start with the simple stuff - the packaging, so you know what to look for in the stores. The dimensions of the box are obviously very small given its compactness. The box has a photo of the PSU at its face, with the modular panel exposed to show interested buyers that this is a fully modular power supply. Below it we can see and a brief description of its features.



Around the back, you will find an diagram about length of cables and connectors on them, dimensions of SFX L PSU, power specifications table, and the serial number. The PSU is wrapped in bubble wrap for enhanced protection against rough shipping. We would prefer to see the use of packing foam instead, which offers even higher protection.



Inside the box, with the power supply you are also provided with the cables, two sets of fixing bolts(one for mounting the PSU into the chassis and a second one for attaching the provided ATX bracket) a product manual, and a mounting plate. The latter allows you to mount the unit into a normal ATX case. A regional power supply cable is also supplied.



It include's a total of four eight-pin (6+2) PCIe connectors for full multi-GPU support , six SATA headers, and three Molex ones. All cables are stealth and flat, meaning that, thanks to their black wires, they're easy to hide inside of a case with a black-painted interior. We prefer flat cables over the typical, round-shaped cables since the flat versions block less airflow and make cable management easier.



All cables are short, since this PSU is designed for smaller enclosures. Longer cables would only cause trouble for routing and management. The distance among connectors is pretty long, which can prove to be helpful, even in small cases.





A Closer Look Outside

Although the PSU has an increased depth of 3cm compared to SFX units, it still has compact dimensions thanks to its limited width and height, which are kept at the same size. With its all-black design, the SFX L Power 600W is not designed to stand out.



Cooling the unit down is a single 120mm fan. The logo at the center of the fan grill looks nice.



On the side of the power connection in the case, ventilation is made in the form of a honeycomb structure and there is also a master power switch here. The power specifications label covers almost entirely one of the unit's sides. The chart has been reproduced in the specs table towards the beginning of this article. The be quiet's name and company logo are stamped into the casing on the top.



The company name is embossed on the right side of the unit. A Warranty Void sticker is present too. Around the back, you'll find fully modular connectors. There's a split 24-pin, two peripheral connectors, as well as three 8-pin for the motherboard and PCI-E devices. Everything is labelled and as such, you'd find it hard to go wrong.




A Closer Look Inside

Got your SCUBA gear on? Time for a deeper dive. To remove the top cover, simply unscrew four screws, one of which is hidden by the warranty seal. This operation obviously invalidates the coverage offered by the manufacturer, which is why we do not recommend performing it for the first 3 years of the power supply's life. The layout of the elements inside the power supply demonstrates the competent approach of the developers to the cooling issue. The main heating elements are located along the flow of air leaving the PSU, and not across it, as it is implemented in some models of the SFX format. There is also a minimum of wires inside the power supply - everything is assembled on jumpers or contacts without the use of flexible connections, which allows freeing up space for more efficient air exchange inside the power supply case, as well as reducing aerodynamic resistance to the air flow created by the fan. At the same time, there is a noticeable pile-up of elements near the exhaust hole in the power supply case, which will create additional resistance to the outgoing air flow. The design of the power supply is fully consistent with modern trends: an active power factor corrector, a synchronous rectifier for the + 12VDC channel, independent switching DC converters for the + 3.3VDC and + 5VDC lines. High-voltage power elements are installed on a medium-sized radiator. Transistors of a synchronous rectifier are installed on the back side of the main PCB, elements of pulse converters of + 3.3VDC and + 5VDC channels are located on a daughter PCB installed vertically.



Be Quiet! entrusted their SFX L units to High Power, a known OEM who often is behind the German company's PSUs. There is an EMI filter on the left side,the first part is directly on the AC plug.



The first part of the EMI filter is on the AC receptacle. It consists of two Y caps and a single X one. It continues on the main PCB with two more Y caps, an additional X cap, two CM chokes, and an MOV (Metal Oxide Varistor). One GBU1506L bridge rectifier is installed on the heat sink.



The APFC converter uses two Toshiba TK16A60W FETs FETs and a single Infineon IDH08G65C5 boost diode. The bulk cap is provided by Rubycon. Disappointingly, it suffers low capacity and a mere 85C rating. High Power should use a 105C cap with much higher capacity, enabling a decent hold-up time. Then again, the higher the bulk cap's capacity, the higher its energy losses due to increased ESR (Equivalent Series Resistance).



The primary side APFC circuit control core is Infineon ICE3PCS01G, which is set on the daughter board next to the APFC capacitor.



APFC power components mounted on the heat sink use 2 Infineon IPA50R140CP fully insulated package Power MOSFETs.



The daughter board next to the primary side LLC resonant tank has Infineon ICE2HS01G which is responsible for controlling the primary side HB-LLC and the secondary side 12V synchronous rectification.



On the secondary side of the 12V power stage on the back of the main circuit board, 6 TOSHIBA TPHR8504PL MOSFETs are used to form a full-wave synchronous rectifier circuit. Flow capacity and assist in heat dissipation. The rectangular solder joints next to the MOSFET can also conduct heat to the metal heat sink on the front of the circuit board.



The sinks installed on top of the +12V FETs feature two thermistors. One is used by the fan control circuit and the other provides temperature data to the supervisor IC for over-temperature protection.



On the back of the DC-DC circuit daughter board, on the top is the Anpec APW7159 dual-channel synchronous step-down controller, 2 sets of power stages (1 set each for 3.3V/5V) are located on the left/right side, each group uses 2 Infineon BSC0902NS MOSFETs, 1HS +1LS configuration.



Secondary side power management circuit daughter board, using Siti PS223 power management IC, responsible for monitoring output voltage/current, receiving PS-ON signal control and generating Power Good signal.



The back of the modular output socket board is tinned to increase the current-carrying capacity, and no insulating partition is added. 4 Nichicon solid capacitors are placed on the front of the modular output socket board to enhance the output filtering effect. The lower 3.3V / 5V / 12V / GND contacts are connected to the main circuit board with metal plates, 5VSB / -12V / PS-ON / Power Good/Remote sense, etc. are connected by wiring.



Two Infineon IPD060N03L MOSFETs are set at the output of the 5VSB circuit. When the power is turned on, the 5VSB power supply will be switched from the auxiliary power circuit to the DC-DC 5V output to reduce the power consumption of the auxiliary power circuit and improve the overall conversion efficiency. At the bottom left is the shunt for 3.3V/5V output current detection.



Soldering quality is good throughout and the layout is clean.



The power supply contains a 120 mm low-profile fan - S1201512MB manufactured by Globe Fan. The fan is based on a hydrodynamic bearing and has a maximum rotation speed of 1800 rpm.




Instrumentation used


Below we report the instrumentation used in the test phase for the be quiet! SFX L Power 600W.



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
Scythe Kama Wireless Thermometer
Center 325 sound level meter


Load Regulation

As expected, in the simulation of real use the voltages dropped much less than in the crossload test, especially for the 3.3 and 5 volt lines. The ATX specifications are obviously fully met and each component will receive adequate voltage regardless of the applied load.






Efficiency

The 80Plus Gold certification is confirmed by our test with a fair margin- the maximum efficiency recorded around 300W is close to 93%. This result was by no means taken for granted, especially if we consider the very limited space available which therefore did not compromise the quality of the electronics used.




Cross Load

Ripple can easily be measured by an oscilloscope. These show how much voltage fluctuation there is on a particular rail. We tested the rail stability of the 3.3 volt, 5 volt and 12 volt rails. The ATX 12 volt specifications state that ripple from peak to peak must be no higher than 50 millivolts for the 3.3 volt and 5 volt rails, while the 12 volt rail is allowed up to 120 millivolts peak to peak to stay within specifications. Millivolt figures are stated to the closest increment of 5 given their variability.



Once again, be quiet! absolutely dominates here, scoring exceptionally low ripple and showing that despite its compact size, this PSU can deliver clean and stable power.






Cross Load

The crossload test aims to squeeze the lines of interest to the maximum one at a time. The supplied voltage remains with a good margin within the limits imposed by the ATX standard, therefore there is no problem for the peripherals powered by the be quiet! SFX L Power 600W. For this reason we have recorded drops of more than 3% on the lower lines, while that on the 12V line remains below 2%, a value considered as a parameter of excellence. The difference between the voltage recorded in the absence of load and that observed at maximum power is for the voltages of 3.3 and 5 volts almost exclusively due to the drops on the cable, in fact the voltage measured directly on the modular connection panel remains close to that of departure. In any case, the supplied voltage remains with a good margin within the limits imposed by the ATX standard, therefore there is no problem for the peripherals powered by the SFX L Power 600W.












APFC

The power factor control system (APFC) is confirmed as excellent for the be quiet! SFX L Power 600W, achieving a remarkable result despite the section reduced to the bone. We remind you that the reduction of the phase shift between the voltage wave and the current wave, operated thanks to the combined action of the inductor and the input capacitors, allows to minimize the apparent power which is of no use, but negatively affects the electricity detected by the meter.



During the overload test we ascertained that the protection system used by be quiet! for the SFX L Power 600W model uses a different behavior, depending on whether the overload is sudden or gradual. In fact, a rapid increase in the required power involves switching off the power supply already above 630W, while with a gradual increase we were able to get close to 742W with a power absorbed by the electricity network of just over 816W, which translate into a efficiency close to 91%. We can therefore confirm the presence of an adequate protection system against overload and an effective oversizing of the internal components.




Temperature

The Globe 120mm fan is great as it can be verified above with the combination of low noise and fantastic temperatures, rising to a peak of around 8c over ambient at full load.




Noise

The power supply is quiet right up to 70% load when the fan starts to speed up to compensate for rising temperatures. at 450W it rates around 42 dBa rising to around 44dBa at full load. Under normal operating conditions the unit will be rating below 40 dBA which is basically silent in most living environments.




Final Thoughts

be quiet! has yet again proven why they are the premier power supply manufacturer in Germany. Not only for Germany, but they do indeed deserve the international attention and spotlight for exceptional units and build quality. This unit steps out from the typical product line and is truly inspiring on what may come from the company in the future. Sitting between standard ATX and SFX in terms of size and volume, SFX-L seems like a great middle ground, as you're able to retain 120mm fan support for better airflow and lower noise while still reducing footprint considerably compared to an ATX model. The fan profile is not aggressive and this partially compensates for the lack of a semi-passive mode. be quiet! ensure ATX compatibility by including an SFX to ATX adapter, although the shorter length cables may prove restrictive in certain larger ATX chassis. On a build quality level, the unit is well finished, and the pure modular design means it will cater for system builders dealing with restrictive routing space inside a smaller chassis. We do love the be quiet! cable design ? these cables can be bent and routed into some very tight spaces, which would otherwise prove difficult. Technically, the unit is solid and delivers quality power across the spectrum. Load regulation rates highly and the supply doesn?t exhibit any concerning issues. Ripple suppression while not class leading, rates well within industry parameters and the 600W model we reviewed today dealt with difficult cross loads without any problem. A three-year warranty isn?t something of a combo, 5 years would be more confidence-building even if, in general, the brand is one of the more reliable, and competition doesn?t exaggerate the allocation of warranty time in this category.



The price, at 95 Euros it is a clear win for be quiet! as this price range is where most SFX L 500W units reside. Remember, compact dimensions can significantly increase PSU production costs, affecting the final retail price. The be quiet! SFX L Power 600W is probably the finest SFX L power supply on the market right now. Equipped with 600W of power, more than enough for any high-end and overclocking gaming rig with a single GPU, 100% Japanese 105c capacitors, quality regulation, the usual electrical safegaurds, a fan for ultra quiet performance at lower loads, fully modular design and that compact SFX L form factor, the SFX L Power 600W is certainly an attractive unit.