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Performance, Value, Noise & Efficiency
Performance Rating
The following graph shows the RM850x's total performance rating, comparing it to other units we have tested. To be more specific, the tested unit is shown as 100 percent, and every other unit's performance is shown relative to it.
Very good performance allows the RM850x to approach Corsair's higher-end HX850. The EVGA 850 G3 achieves a notably better score in this metric, but it loses big time when we compare noise output.
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 white RM850x costs more because of its individually sleeved cables, and our performance-per-dollar calculation reflects this.
Noise Rating
The graph below depicts the cooling fan's average noise over the PSU's operating range, with an ambient temperature between 30°C and 32°C (86°F to 89.6°F).
This is where the RM850x shows its strength. EVGA's 850 G3, its main competition, isn't available in all-white and is miles away when it comes to our noise measurements.
Efficiency Rating
The following graph shows the PSU's average efficiency throughout its operating range, with an ambient temperature close to 30°C.
Efficiency-wise, this platform isn't among the best in its class (mostly because of lower efficiency levels under light loads).
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