Are you trying to use multi-rail PSUs? My guess is yes. Use a good quality, Gold or Platinum single rail PSU for all mining rigs. Seasonic, Corsair and EVGA make the best PSUs for mining in my opinion.
I have to throw a shout-out for XFX supplies. They're priced well, single rail, and the higher output units are made by Seasonic.
I have an XFX Pro 1000w that has been absolutely rock solid running a Bitfury rig for the better part of a year. But as with any manufacturer, stay away from the low-end multi-rail units.
I love the Corsair AX1200i PSUs too but the EVGA Supernova 1300 G2 are $100 less and have excellent reviews. They are Gold rated but some reviews say they could be easily be Platinum rated. But alas, the don't have the fancy USB interface/GUI that the Corsairs have. But I don't find that useful for Bitcoin mining rigs anyways.
true enough, the UI is pretty pointless in terms of mining... i've never owned an EVGA, i'll need to have a look into that this coming winter when the space heaters come outta the cupboards
