Can I run a 3070 Nvidia FE card off one 4x 8pin (6+2) PCIe cable included with my modular 750 B3 Psu. 3070 max load with PCI slot as well as PICeCable is 220. 
 
Included 12 pin adapter is only partially filled and will not work on a 3080 so there isn't any point on running a second cable from PSU right?? Just use the one 4x 8pin (6+2) PCIe cable from the PSU should be fine "On the closeup of the 12-pin adapter, you can see how only half its pins are populated. This ensures that on a RTX 3080/3090, this adapter will not work, as those cards require power on all pins." 
www.techpowerup.com/review/nvidia-geforce-rtx-3070-founders-edition/4.html
 
Reason being is I have a SG13 mini ITX and don't want to run a second cable that will further slow airflow from the front fan. As is with my old EVGA GeForce GTX 1070 SC GAMING ACX 3.0 everything is running nicely with one cable.
 
 
I am really happy with my SG13 case and this was the only GPU that would fit in it. I don't have the card until Sat but want to be ready.   www.reddit.com/search/?q=sg13

Thanks sorry when you get the 3070 FE it is very obvious it only needs one connector not both like my old 1070. There were discussions about the 3070 needing two separate cables but they must have been concerning the 3rd party cards. Man this 3070 is tiny compared to my EVGA 1070 sc. There is ample room for a longer card wish the 3080 wasn't 2.5 thick.