They suggest following:
750 Watt Power Supply is required.
1X150 Watt 8-pin PCI Express power connector is required.
But it's hard to tell. It supports 2 x 6 pin, whereas Your GPU would require an adapter [2 x 6 pin to 1 x 8 pin, get it on ebay for few bucks, or anywhere]. Not sure if it'll keep Your system stable, it should, but...