Can i run this video card?

Im buying a new video card for Xmas and right now i have a 256mb Video card i want a 512mb...........

THe video card im getting says





I have opened my PC and idk how to calculate the watts..

Its says "A minimum 300W or greater system power supply (with a minimum 12V current rating of 18A) "







My Power supply says

AC input 100-127 / 220-240v ~6/3.15A 50-60 Hz

DC output +5v --------/ 15A MAX -12v ----0.3A MAX +12V -----14A MAX

+5v(SB) ------2A MAX + 3.3V -----13A MAX







So will it run........if not can you find me a 512mb VC on this website ..www.frys.com|||I think it will work.|||ask your motherboard manufacturer if it it is compatible.