Thank you for the advice. How would I go about connecting two PSU's to the same rig? I assume the 1000w would be used to supply power to the motherboard and 3 cards, and the 750w for the remaining 2 cards. Do I need any special power connectors for it?
I think they both require 1 x 6 pin and 1 x 8 pin connectors so you have to be sure that you can connect them all with the available cables from the PSU's.
i think you can do it with a single 1300w from evga, you just need to undervolt your 390 to -100mv so around 200w each at maximum, in this way you can avoid all the trouble with two psu, because i've read bad story about two psu and a h81 pro btc, when using double molex
That's the better decision, but I'm not sure if he can do it...