I've currently got a Dell Precision 690 and recently acquired a pair of memory risers (JF806/JF807) and would like to run them with my modern 1KW modular power supply. Do the power cables connect directly to the original 1KW power supply or do they connect to the motherboard? Does anyone happen to know the part numbers of the cables and/or a source to find them? Any help would be greatly appreciated.

Thanks in advance!