how much that gonna set you back? I just built (on thursday)
AMD Phenom II x4 black edition 3.2ghz
ATI Radeon Sapphire hd6850 toxic edition
6gb RAM
Windows 7
500gb SATA III 6gb/s HDD
Obvs other stuff. That whole pc set me back only 600 quid and its a fucking BEAST <3
I know sooo many people bum intel processors but they're really expensive compared to the phenom IIs. My processor was 113 quid.
Deffs build yourself, but keep in mind it can get fiddly so if you have any friends who know computer stuff, get them with you to help for your first build.
AND, go to scan.co.uk. Best place for PC stuff in the UK imo