jkarateking :
Is this R9 290 good enough. It was the cheapest:
http://uk.pcpartpicker.com/part/asus-video-card-r9290dc2oc4gd5
Let's start off with this, first.
http://gpuboss.com/gpus/Radeon-R9-290-vs-GeForce-GTX-780
This shows that performance is, on the 780, better, and for cheaper. RIGHT NOW, there's a sale on a GTX 780 from EVGA (A very reputable and well-known company!) for only 499$/About 298£!
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130951&cm_re=780-_-14-130-951-_-Product
I'd once again highly suggest the Nvidia! I have an AMD card myself, but I experience lots of stuttering and FPS drops, as opposed to my 780 Ti, which has much less, if not any stuttering, and FPS drops of increments so small that they aren't even possibly visible to the human eye!
Get that 780 man, telling you!
(Oh, and with one card, you'll be covered for a few years. If you decide to save up and get another for SLI, you'll be set for a looong time bud.)