what are you on?? too much candy? core 2 duo was a high end cpu a few years ago, it is equivelant to an athlon x2 or phenom X2. nothing power saving about it, its a full power desktop cpu, not a laptop cpu. a core 2 duo processor is a "dual core" processor. You clearly have no idea.
just make sure your motherboard has the appropriate pcie expansion slot, and your power supply is the recommended wattage for the card. and you dont need a 4 core processor for 6xxx series gpu's, that is a lie.