Performance, Noise and Efficiency
The RM850x achieves higher overall performance, mostly because it has perfect ripple suppression and slightly better load regulation than the RM850. Nonetheless, the RM850 performs well and you shouldn't forget that it had to have a performance gap with the RM850x or else it would create strong internal competition in Corsair's portfolio.
The graph below depicts the cooling fan's average noise over the PSU's operating range, with an ambient temperature between 30 to 32 degrees Celsius (86 to 89.6 degrees Fahrenheit).
The RM850x takes the lead here but the RM850 scores second place, which is a great result.
The following graph shows the PSU's average efficiency throughout its operating range with an ambient temperature close to 30 degrees Celsius.
The overall efficiency score of the RM850 is a bit higher compared to the current RM850x model.
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