Introduction

We would like to thank FSP for supplying the review sample.


The FSP Dagger Pro 650 W is among the very few SFX PSUs featuring two EPS connectors, which makes it suitable for high-end mainboards and power-hungry CPUs. The new Dagger line from FSP consists of two models with respective capacities of 550 W and 650 W. In today's review, I will take a detailed look at the stronger unit with model number SDA2-650.



The SDA2-650 is fully modular and achieves a high power density score because of its compact dimensions. Currently, the highest-capacity SFX unit is Corsair's SF750, but still, 650 W out of such a small platform is an impressive feat. However, what matters the most is keeping performance high in all areas, and not compromising anywhere.

The SDA2-650 comes with a 92 mm double ball-bearing fan. In terms of dimensions, this is the largest fan an SFX unit can take. The previous Dagger with a capacity of 600 W couldn't keep up with the competition mostly because of a ripple problem on its +3.3V rail, so I am eager to see whether this new model can face off against the competition, which includes the EVGA SuperNOVA 650 GM also made by FSP but based on a different platform.

Specifications

*The SDA2-650 is not certified by Cybenetics, but based on my results, it meets the cited Cybenetics certification.

Cables and Connectors

The two EPS connectors affect how many PCIe connectors there are, of which there are also two. Strangely enough, the ATX and EPS cables are long, while the PCIe and the peripheral cables are short. Finally, the distance between peripheral connectors is short at 100 mm, but I will let this slide since SFX PSUs are for small cases.

Component Analysis

Although the previous Dagger model used a half-bridge topology, which is among the most common nowadays because it offers good performance, FSP decided to go with its favorite topology with this unit, Active Clamp Reset Forward (ACRF). I am not that fond of ACRF because I thus far haven't seen a platform that uses it offer top performance on par with half-bridge and full-bridge topologies. On the other hand, ACRF platforms can achieve very long hold-up times with small bulk caps, which is a big advantage for compact PSUs.


The transient filter includes all the necessary parts, and there is also an NTC thermistor along with a bypass relay.


The APFC converter includes two FETs and an equal number of boost diodes, while the bulk cap is by Chemi-Con. The main switch is an Infineon SPA17N80C3, and the other switch is an IPD80R2K8CE FET by the same manufacturer.


On the secondary side, two Infineon FETs regulate the +12V rail, and a couple of VRMs handle the minor rails.


The electrolytic caps are of high quality since all of these belong to good lines of respected Japanese manufacturers (Rubycon and Chemi-Con).


At the front of the modular board are several polymer caps by Teapo that provide an extra ripple-filtering layer. The protections IC is installed in this section.


The 5VSB regulator circuit.


Soldering quality is good.


The cooling fan uses a double ball-bearing, which is the best choice for compact high-capacity PSUs.