Bitfenix Fury Gold 750 W 23

Bitfenix Fury Gold 750 W

Voltage Regulation, Hold-up Time & Inrush Current »

A Look Inside & Component Analysis

Before reading this page, we strongly suggest a look at this article, which will help you understand the internal components of a PSU much better. Our main tool for the disassembly of the PSU is a Thermaltronics TMT-9000S soldering and rework station. It is of extreme quality and is equipped with a matching de-soldering gun. With such equipment in hand, breaking apart every PSU is like a walk in the park!

Using the Aurum platform, Bitfenix teamed with FSP for their Fury PSUs. We come across this platform in the EVGA SuperNOVA NEX750G, and it simply failed to impress us. The primary side of this platform uses the Active Clamp Reset Forward (ACRF) topology in which two mosfets are used; one plays the role of the main switcher (Q1) and the other is the reset switch (Q2) that disconnects the main capacitor(s) while Q1 is active. We find a type of group regulation scheme that performs poorly with highly unbalance loads among the rails in the secondary side.

The first part of the transient filter is right at the AC receptacle and only includes a couple Y caps. The rest of its parts are located on the main PCB: two CM chokes, a small DM choke, and four X and Y caps. The design is like in the SuperNOVA unit since it doesn't include an MOV (Metal Oxide Varistor), which we don't approve of. However, FSP says the MIA IC this platform uses to offers over-voltage protection as it can absorb excess surges coming from the power grid. We would have still highly preferred it if they had utilized an MOV and the aforementioned IC instead. On the solder side of this area is a CAP004DG discharge IC that blocks current through the X caps discharge resistors when AC voltage is connected, which increases efficiency.

The single bridge rectifier is bolted to a small dedicated heatsink and is surrounded by tape.

The photo above shows the NTC thermistor that provides protection against large inrush currents and the diode that bypasses it once the PSU starts.

In the APFC, two Infineon IPA60R165CP fets are used, along with an STTH8R06FP boost diode. Right behind the boost diode is the 5VSB regulation mosfet, a GE03N70T that supports up to 3.3A continuous drain current at 25°C and only 2.1 A continuous drain current at 100°C, which will have it operate beyond its limit with a full load at 5VSB. The hold-up cap is provided by Rubycon (450 V, 390 µF, 105°C), and it manages to provide a long hold-up time because of the topology used.

The role of the Q1 fet in the ACRF topology is played by a SPA17N80C3, and we find a FQPF3N80C fet taking on the role of the Q2 fet. The FSP 6600 IC for which there is no public documentation acts as the APFC/PWM controller.

A synchronous design where two mosfets that are cooled by a small heatsink handle the generation of +12V is used in the secondary side. The 5V and +12V rail are regulated by two IPD031N03Ls, while 5V delivers the 3.3V rail through a DC-DC converter and the help of two IPD031N03L fets. So a group-regulated scheme is utilized for the generation of the rails, which will seriously hamper this unit's performance in our crossload tests.

As is the norm for this platform, the PWM controller responsible for the secondary side is a proprietary FSP 6601 IC. All filtering caps are also provided by Nippon Chemi-Con (KZE and KY series). These caps are rated at 105°C.

The supervisor IC is a Weltrend WT7527. It supports OCP for up to two +12V rails. This unit, however, only comes with one.

While the EVGA SuperNOVA NEX750G comes with two large Chemi-Cons on the back of its modular PCB for better ripple suppression, the Fury-750G comes with no caps there, which is a shame, although it could help the unit achieve higher efficiency. Bitfenix has thankfully installed an electrolytic cap onto the front of the modular PCB. While Chemi-Con provides the cap, the NEX750G is still better off here as it uses several polymer caps instead of a single electrolytic cap.

Sleeving might be nice, but these wires have been left bare, which is not a nice sight to a reviewer's eyes. Bitfenix should have used heat-shrinks to keep these under wraps.

Soldering quality on the main PCB is decent, although there are a few sloppy spots. We also spotted three current shunts under the +12V islands; however, these +12V wires have been shorted together to form a single +12V rail.

The cooling fan is provided by Protechnic Electric, and its model number is MGA12012HF-A25 (12V, 0.45A, 2400 RPM, 84.8 CFM, 37 dBA, 155g). It is a high-quality FDB (Fluid Dynamic Bearing) fan, so it will last for a very long time regardless of whether the unit operates around the clock or not.
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