Hm, i think the best choice would be the 8pin to 2x 6+2 pin adapter. I would use this twice, of course on 2 different ports.

Looks safer to me than SATA to 6pin.

Or what do you think its the most safe config? Remember: The Card draws 65-70 watts only (limited!)

edit: just saw the first link is a cpu pin to gpu pin. Is there something like a 6+2pin to 2x 6pin adapter?