LOL - You must have gotten the wrong info packet in the box. Theres no way a gt440 needs 23a - it doesnt even have an external power connector on it. its powered soley by the pcie slot which is limited to 75w. As long as your pc has a pcie v2 (or higher) x8 or x16 slot you will be fine.
thanks for your answer, and what could happen if i have a pci e in it´s first version?... gulps xD