Corsair just struck a new blow in the battle against wasted energy, unleashing a pair of power supplies that boast a 90% efficiency rating. The HX850W and HX750W, part of the Corsair Professional Series of PSUs, meet 80 Plus Silver certification standards for reducing wasted energy and lowering the amount of excess heat generated. The company claims its models are built using industrial grade electrical components, and enthusiast site HardOCP notes that the HX850W's packaging now advertises solid polymer capacitors; quality components cost more but can certainly do wonders for a PSU's efficiency.

The 80 Plus performance specification required power supplies to be 80% or greater energy efficient at 20%, 50% and 100% of rated load with a true power factor of 0.9 or greater. Last year, the group unleashed an update to the spec with bronze, silver, and gold labels to distinguish among PSUs with even higher levels of efficiency. The silver certification is awarded to power supplies that are 85% efficient at 20% utilization, 88% efficient at 50%, and 85% efficient at 100%. To earn gold (only 40 models have to date), efficiencies requirements are 87%, 90%, and 87%.

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