I've had one of the stock fans fail.
Yes I had read they could cope with more then the 750 so they are within operating limits with the 4 ants.
I'm drawing 1680 Watts at the wall according to my monitor.
As they don't keep the ants cool enough even running at 190-200 gh they are only at about 34 with the new fans, I run two fans in case one cuts out, thus the ants don't cook them selves.
Also i'm not to sure how reliable they are, I've chosen a fan that I know is regularly used on servers and has a good reliability track record.
you have done a nice job on temp control!
But you are overloading your psu. and 1680 watts is not acceptable on a 15 amp 120 volt circuit for 24/7/365 work.
15 amp x 120 volt =1800 watts x 80 percent = 1440 watts1680 on a 15 amp circuit = bad bad bad
and running your psu to redline is also bad bad bad bad.
I smell melting rubber bro! but I really like the cooling ideas the rack is also nice
If you go back and read he says he is only powering two Ants off of each 750 PSU so I'm pretty sure his 1600 number is for 4x Ants and 2x PSUs plus a PSU to power the fans.