would the performance of a 3 way crossfired Asus Radeon R9 280X 3GB Video Card be able to handle battlefield for in ultra or high settings? or it doesn't help change the graphics any better than what one card would do?
Unless you use multiple monitors or 4K, this is overkill. Two 280X will handle any game (where Crossfire is supported) at max settings @ 1080p or even 1440p.