Hi I look all over the net about info in how to connect different cpu card like gtx, some need only 6 pin connector, others need a 6pin and 8pin and some just 8pin, my question is when need a 6pin where draw the power?, when it 8pin where plug it? and when it both same question. i read it not a good way to take a mini 6pin to 8pin. I am confuse between all cable pin and power needs.. some on know the safe way to plug? I want a gtx1060 and it say it need a 400w power computer, but mac pro is only 300w. i saw most card require a 400w.