The Corsair HX1000W is so far one of the best power supplies I have tested and the only area I could find fault with is power factor at 230VAC. The feature list for the HX1000W, at least the way I read it, claims a power factor of 0.99 at all times. When supplied from 230VAC the power factor is never better than 0.96. This is really only a minor failure and will have no impact on the way the power supply performs in the real world. What the vast majority of PC users want are clean, stable DC rails and the HX1000W provides both even at 1000W. The DC voltage load regulation and efficiency are excellent and AC ripple levels well within the ATX12V specification.



Link: Overclockersclub