Re: Little advice for battlefield 3?
Welcome to the forums.
Any mid to high level graphics card requires a decent power supply. Usually the requirement pages of graphics cards have the kind of power supply that is recommended. It is a god idea to go over the wattage that is specified. So, if a 500watt power supply is recommended for a certain card, better to go 600-700, just to be sure.
Others can recommend specific cards as I am not 100% knowledgeable on the current generation.