hello
Something very strange happened to my 6 month old Corsair AX 860 PSU
I'm mining steady since months with no problem @ 1830kH/735W av
I've got 3 undervolted + a little overclocked sapphire 7950
with one mobo Asrock970 extreme4 + normal PPCIe risers
Here's your problem, sir. You're running your PSU at 85.4% total load, no wonder it burnt out! PSUs are fine with this for a few hours at a time if you're gaming or doing something intensive, but not for mining for any good stretch of time. I'd recommend at least a 1000W PSU if you're going to be mining with three cards.