Super Flower Leadex Gold 550W PSU Review

Super Flower has made quite an impact on the PSU market. Its Leadex platform enjoys huge popularity, both under SF's brand name and other companies like EVGA. The newest Leadex Gold-rated PSU with 550W capacity is on our test bench today.

By Aris Mpitziopoulos
published

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Performance, Performance Per Dollar, Noise and Efficiency Ratings

Performance Rating

The following graph shows the total performance rating of the PSU, comparing it to other units we have reviewed. To be more specific, the tested unit is shown as 100 percent, and every other unit's performance is shown relative to it.

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As expected, the SF-550F14MG's performance is similar to EVGA's 550 G2, which uses the same platform but with only Japanese caps. In general, this Leadex-based unit fares well, easily taking the lead from most of the competition. Only the super high-end Seasonic fanless unit performs better (along with the Platinum-rated Leadex platform upgraded with better components to achieve higher efficiency).

Performance Per Dollar

The following chart may be the most interesting to many of you because it depicts the unit's performance-per-dollar score. We looked up the current price of each PSU on popular online shops and used those prices and all relative performance numbers to calculate the index. If the specific unit wasn't available in the United States, we searched for it in popular European Union shops, converting the listed price to USD (without VAT). Note that all of the numbers in the following graph are normalized by the rated power of each PSU.  

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The price of this unit in the EU market, where it is available, is very good, allowing it to score well. Take into account that the EVGA 550 G2 uses only Japanese caps though, whereas Super Flower's contender has some Taiwanese (CapXon) caps.

Noise Rating

The graph below depicts the cooling fan's average noise over the PSU's entire operating range, with an ambient temperature between 28 and 30 °C (82 to 86 °F).

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The SF-550F14MG's low-speed fan and its relaxed profile under normal environmental conditions enable very quiet operation. In this section, the Leadex unit beats its EVGA sibling and the difference is notable. Nonetheless, the quietest 550W contender is the Platinum-rated version of this platform, which typically operates in fanless mode, making it ideal for super-quiet systems.

Efficiency Rating

The following graph shows the average efficiency of the PSU throughout its entire operating range, with an ambient temperature between 28 °C and 30 °C.

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The SF-550F14MG takes last place against its competition in average efficiency. It might be a true Gold-rated unit, but there are other 80 PLUS Gold supplies that feature higher overall efficiency.

Aris Mpitziopoulos
Aris Mpitziopoulos
Contributing Editor

Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.

10 Comments Comment from the forums
  • blazorthon
    Granted the EPS and PCIe wires don't see very high current in most situations (especially the EPS with Haswell or Skylake CPUs), I hardly ever see other PSUs using thinner gauge wires, so I can't imagine it saving enough money to be worth going thinner than the recommended 18 gauge wires most other PSUs have regardless of capacity.
    Reply
  • Quaddro
    Why crapxon?
    I'm tired to see bulged crapxon..

    If this one use jap caps, it'll be absolutely perfect..
    Reply
  • iam2thecrowe
    I wonder if it's just a faulty unit with the low hold up time?
    Reply
  • Mac266
    I wonder if it's just a faulty unit with the low hold up time?

    My first thought too
    Reply
  • Aris_Mp
    The APFC caps have the advertised capacity so there is nothing wrong with this PSU.
    Reply
  • mctylr
    Unfortunately, the bridge rectifier's markings are on its hidden side, and we try to avoid desoldering these type of parts since they are extra sensitive to increased heat

    Huh? Since when are bridge rectifiers particularly heat sensitive? I would say that bridge rectifiers are not worth the hassle to desolder, unless you suspect it was an underrated part.

    APFC controller is an NCP1653A provided by ON Semiconductor. It's installed on a small vertical PCB and is covered by insulation tape in order to decrease EMI noise.

    That looks like paper and vinyl / PVC electrical tape wrapped around the vertical PCB, which provides electrical isolation only, I doubt it would make measurable difference in EMI.
    Reply
  • Aris_Mp
    According to my experience so far they are, unfortunately.

    This provides some EMI protection. There is no need for electrical insulation on this board. As for the degree or EMI protection I can examine this with my EMC probes (once I find the time to do it).
    Reply
  • Andi lim
    this review said uses a half-bridge topology, I only see one main capacitor. half bridge usualy uses 2 main cap and 2 main switcher right ?
    Reply
  • Aris_Mp
    the number of APFC caps has nothing to do with the primary topology. However yes half-bridge uses 2 switchers.
    Reply
  • Andi lim
    You are right, this is half bridge with LLC series resonant converter, nothing wrong with the primary capacitor.
    Reply