Gigabyte GA-P55-US3L P55 Socket 1156 8 Channel Audio ATX Motherboard
ASUS HD 4670 512MB DDR3 DVI VGA HDMI Out PCI-E Graphics Card
Samsung SpinPoint F3 500GB Hard Drive SATAII 7200rpm 16MB Cache - OEM
Corsair 550W VX Series PSU - 120mm Fan, 5 Year Warranty
Casecom 6788 Black Mid Tower Case
120mm Black Case Fan - 4 pin connector
Titan TTC-NK85TZ Fenrir CPU Cooler
Titan TTC-C10 clip for Intel LGA 1156 for Fenrir TTC-NK
It's alright, but the i7-860 is a much better CPU for non-gaming.
I'd switch the cooler for a Coolermaster Hyper 212 or Sycthe Mugen-2 Rev. B (see this article).
Keep in mind that the board you choose is the older Gigabyte, and they had a problem or causing total failure when trying to go for a huge (4 GHz+) overclock. The problem was fixed with the P55A series.
Not so sure about that case. I can't find it on Newegg. You might want to consider the Antec 200 or Antec 300. Both are high quality, low priced cases.
Go with a core i7-860, they offer better performance for workstation PCs. Secondly if it is a workstation PC, why is it not graphical intensive. The definition of a workstation PC is one that has high graphics capabilities, fast CPU, and memory for running multiple applications. Workstations are used for rendering and calculations, and other hardware intensive computing. The i7-860 will work great, but you still need a good GPU backing it, and also you might want to go to 8gb if this is going to be a true workstation PC.
sorry i was vague, you can't rate something if you dunno what against:
budget is about £400 without vat but its currently £500 have i over speced anything?
usage is calculation workstation, databases and multi tasking (hence the budget graphics)
Hopkiller, surely those workstation roles (Graphics or Calculation) are totally different and could be filled by two different budget systems or one expensive one? i know everyone imagines them as rendering machines, thats not what i'm after, its the calculation side, and having lots open