Did Asus bundle molex with the card? If not you can buy it yourself (2X 4-pin to single 8-pin power connector). Usually such card use 2 6pin but a single 8 pin is equal 2 6pin in terms of power supplied. Personally I think such design is better due to less cable involved but some PSU only comes with 6 pin which could be thereason most gpu vendor still use 2 6pin config on their card