It's coming out at £643.62. Could probably knock £100-£200 off that if you didn't care about making it as quiet as possible and getting a slightly less awesome motherboard. The motherboard would perform the same, just without some of the fancy features like on the fly overclocking in Windows.
Everything apart from the PSU (Dabs) is coming from Amazon.
I found this site if you want to spec up a PC and see what the damage is. It works out pretty well.
http://pcpartpicker.com/uk/parts/partlist/