The overall performance that the C650 achieves is close to the Seasonic Focus and Corsair RM models, but the RM650x, the XPG Reactor 650, and the EVGA 650 G3 are notably better. Nevertheless, the G3 has been already replaced by the inferior G5 line, so it won't be a threat anymore.
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 C650 manages to remain quiet even under harsh conditions (like high loads and increased operating temperatures). Still, the king of this category remains the dead silent Corsair RM650x.
The following graph shows the PSU's average efficiency throughout its operating range with an ambient temperature close to 30 degrees Celsius.
The C650 takes the lead here from its main opponent, the RM650x, but loses to almost all the other offerings in this category. With only exceptions, the first two units from EVGA and XPG, the differences are not so high.
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