I am using MSi 1070 TI's which have 8 + 6 power connections.  I ran a dedicated 8 (6+2) pin to each one.  Then ran a third 8 pin VGA  and I used a 8 pin splitter (the ends are 6+2) for the 6 pins.

https://www.amazon.com/gp/product/B075HTCV9S/

Cheers!