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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.
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.
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).
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.
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.
