Converting SATA to 6 Pin?

Hi,

I ordered all the parts for a gaming rig and after the long wait it finally arrived, but now i have a problem. My psu doesnt have enough connections for my graphics card.
My graphics is AMD 6870, it requires two 6pin connections for power. My PSU doesnt have any and only two 4 pin connections. The fact i only have two 4 pins means the molex adapters that came with the card wont solve the problem as i need four 4pin connections for them.

Long story short, i have an old psu with 6pin and 4pin connections. Is there anyway i could convert one of my extra SATA connections on my new PSU into one of those, like swap the heads?

(Also, my old PSU isnt powerful enough and im not interesting in buying anything online that would solve this problem simply because ive waited too long for this and delivery to ireland for any of these things would take too long, so for now thats the last resort.)

Any help would be appreciated, i was like a kid at christmas when this thing arrived so you can imagine how im feeling now.