Enermax Galaxy DXX 850W EGX850EWL Power Supply Review
 

We can see that heat does have some effect on the voltage output and overall efficiency of the Galaxy, but the effects are minimal. We also find that the Galaxy can put out almost 850W even when temperatures exceed 45°C. The most noticeable difference between my cold and hot box tests would have to be the noise I observed during the hot box tests. The fans became audible at 246W and was almost unbearable at 624W and up.

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