Chad Smith wrote:Thanks for the reply Jerry. Do I need to plug in all power cables into the 6900xt? Two 8 connectors and One 6 connector? Do I use one of the 8x cable that splits into two 8x at the end to plug into the card?
You should fill all the connectors on the card. So if it has 2 x 8 & 1 x 6 ports then you need to fill those. My AMD 6900XT only needs 2 x 8, but cards do have varying power needs and ways they arrange that power so if yours needs 2 x 8 + 1 x 6 then make sure they're all connected.
As for whether to use an 8 -> 8 versus an 8 -> 2 x 8, in general (not specific to the Mac Pro which I have no experience of), I prefer to use 8 -> 8 cables rather than split cables, to avoid putting too much load on one cable.