EVGA GeForce 560 Ti Wattage?

I am planning to get this card,

http://www.amazon.com/EVGA-GeForce-Mini-HDMI-Graphics-0... 560 2048

What wattage would it have/need? If this question cannot be answered, Can you please tell me that it is going to be compatible with the XPS 8300?

460 wattz

(this one)

http://reviews.costco.com/2070/11748801/dell-dell-xps-8...

Will I be able to install the card properly? Without upgrading anything else?