i like the pig tail pcie cable(those that come with 2x 2+6 pin), so with one you can connect two gpu
and the 1300 evga only has two of that, then you need to use two 2+6 pin cable, so 4 in total instead of 3, i like to have less cables as a possible for a clean build
EVGA 1300 G2 has enough 6-pin leads to handle a 6-card rig.
In my limited experience with 2 of them, it's a good PS and kinda overkill for a 6-card RX4xx rig.
it is a bit overkill, but there are not many PSUs at 1100W (which would be an ideal ~70% load). but if dual-mining, you'd be drawing around 130-140w/card, and about 100-150W to the overhead (cpu/fans/hdd/etc). thats ~800-900W, and its good to keep <80% psu load if you plan to run 24/7 for months on end.