Dell proprietary sata power cable P/N

D10: 3880 tower or the like

D12: 3910 tower or the like

these have 8 pin mini sata connector which are Dell proprietary 

1RTKV	ASSY,CBL,SATA,PWR,3.5HD/OD,D10.
NMFDM	ASSY,CBL,SATA,PWR,3.5HD/OD,D12.