Your video card accessories may include an 8 pin adapter of some sort. You could also use the two 6 pin PCIE power supply leads on the video card if they fit until you can locate a 6 pin to 8 pin adapter. The extra two pins are ground contacts. You are still getting the same 12v power, just better grounded with the added 2 pins.
6 pin to 8 pin PCIE adapter. If there is a Fry's or Microcenter store near, they normally carry these 6 to 8 pin 12v adapters.http://www.performance-pcs.com/catalog/index.php?main_page=product_info&cPath=186&products_id=21721&zenid=9a310990863e4862b913de663324b732
Use the power supply's one 8 pin 12v lead to provide power to the CPU.