be quiet! System Power U9 500W PSU Review: Affordable and Quiet

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Performance, Noise and Efficiency

Performance Rating

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The SU9-500 is between the two most popular offerings in the mainstream category, the EVGA 450 BT and the Corsair CX450.

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).

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The be quiet! offering honors the name of its brand, taking over first place in the noise output chart.

Efficiency Rating

The following graph shows the PSU's average efficiency throughout its operating range with an ambient temperature close to 30°C.

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The overall efficiency is high enough, surpassing the corresponding levels of the similar capacity Corsair and EVGA units.

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Aris Mpitziopoulos
Contributing Editor

Aris Mpitziopoulos is a contributing editor at Tom's Hardware, covering PSUs.