High Spec PC for £550 that can run 3D programs

So I need to build a PC for my degree in Games Art which requires a lot of power to be able to run 3D programs like the Autodesk programs and Foundry programs as well as games engines like UDK 4 and of course run them very well. My budget is about £550. I am a total newb at this so if you can recommend any good websites on top of what are the best parts I can buy for my price range it would be much appreciated.

Thanks in advance for helpful answers  

EDIT: the programs specifically I want the PC to run extremely efficiently within the price range are:

Maya 2014
Mudbox 2014
(I will be updating to the 2015 versions when these come out)
Nuke
Mari
Modo
Houdini
Adobe Photoshop CS6
Adobe Premiere CS6
Zbrush 4R6
Marmoset Toolbag 2
UDK 3 (upgrading to UDK 4 though in the next couple of months)

On top of this (something which I have a huge problem with is to be able to render at a decent speed) I want to be able to do quick renders with Arnold and Mental ray.

I also want to be able to run high level games (or to highest level I can within the price range) on it for recreational purposes when I am not working.