[...] the HX series restarts with current apparently at full load. If the reason that caused the fail safe to cut the PSU still exists that component is then place under greater stress then beforehand, where as typically other PSUs ramp the current after being reset. [...]
You're almost as bad as dogie.
Please. No.
Look i'm reiterating what i was told. Do not shoot the messenger. I didn't have to ask. I did it because people were concerned and wanted to know. This isn't my armchair engineering is better than yours, academically trained I'm a design engineer and if I design an electrical, or electronic device I'd consult an expert in that field. In this case this is precisely what I did as, and when the opportunity presented. So quit the abuse, or I quit bothering to share. The fact is unless we can differentiate between the start up characteristics of each individual PSU on the market after they have all been tripped - and bear in mind in every case they had ALL had their fail-safes tripped and required restarts -then we have no scientific ground for recommending one power supply over another. The only thing we do have to go on is the 'long term reliability proving exercise' w.r.t. the Coolermaster V850 being used throughout the entire hosting facility and working faultlessly the entire time. Thus it has the most assured recommendation as the PSU to use. KnC were actually going to buy the HX850, but couldn't secure enough of a volume in time, and taht appears to have purely been by good fortune.
In any case the number of boards we had fail in this manner is insignificant, less than 10 boards out of the thousands manufactured and in the wild, so this is a mute point, but based upon the statistical significance of the corsair hx850's involvement in the occurrences, and the fact the PSU is known to behave in the manner described, it'd be wise to consider avoiding that for a PSU for another known to behave faultlessly...