Graphics card troubles

[Chuckbiggerman]

Guys I really need help. So I bought an xfx r9 390 graphics card to replace my quadro fx 4600. Easy enough to take out and install the r9 but it has 2 power slot things. One has 6 holes and the other has 8. My computer doesn't have an 8 prong wire that fits that. Can I still use it?

 

[LucoTF]

No, you will need to upgrade your power supply im afraid

 

[Chuckbiggerman]

Really? My computer has 2 6prong wires but I only used one in the old card. Do I need to fill up all holes with prongs? Or can I leave some out

 

[scout_03]

name and model of that psu .