I just bought a new graphics card and Power supply i see that the card has a plug in the back of it for 6 pin connector, my power supply has a 4 prong plug what i want to know is do i need a cable to hook my card directly to the power supply? and if so where would i get it? my graphics card is a Radeon HD 6770 and my Power supply is 550W dual fan switching power supply, sorry if this doesn't make any sense I'm trying to explain it the best i can