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 tested in the past. To be more specific, the tested unit is shown as 100 percent, and every other unit's performance is shown relative to it.
Even normal ATX power supplies don't stand a chance against Corsair's new SFX-based model. SilverStone's SFX-G and SFX models can't come close to its performance. Corsair takes over the top spot in this category on its first attempt.
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.
SFX PSUs are expensive, and the SF450 is no exception. Consequently, its performance per dollar score isn't particularly impressive. It does still manage to beat SilverStone's offerings, though.
Noise Rating
The graph below depicts the cooling fan's average noise over the PSU's operating range with an ambient temperature between 28 °C and 30 °C (82 °F to 86 °F).
An SFX unit that features near-silent operation? Once, that seemed impossible. But Corsair manages to achieve it.
Efficiency Rating
The following graph shows the average efficiency of the PSU throughout its operating range, with an ambient temperature between 28 °C and 30 °C.
The SF450 is highly efficient, as the chart above clearly shows. It beats most of the competition at 550W and lower. Compared to Enermax's ultra-high-end Digifanless, which is 80 PLUS Platinum-certified, the efficiency difference is only 1%.