you put it off too long as the prices of the hdd have gone up by £10-£15 for the 1tb(e.g where £40-£45 now £50-£60) and from whats been said likely to go up further.
oliver renault spec looks good tho some changes you could make/price differences since he posted it last week.
the cpu is upto £185 almos £20 increase tho the £168 was a 'this week only' offer I believe tho the normal price was £170-£180 so the upwards trend of the i2500k on ocuk has continued.
mb is upto £134, if you can do without the pci-e 3.0 compatibility have a look at the 2 gigabyte boards I suggested(dependent on if you want sli in future or not).
if you want pci-e 3.0 support then
http://www.overclockers.co.uk/showproduct.php?prodid=MB-191-MS&groupid=701&catid=5&subcat=1990 seems to be the one stulid has beem suggesting in other threads.
the graphics card is down to £210(till tuesday night, goes back up wednesday morning)
the ram is now £48, you could change it to
http://www.overclockers.co.uk/showproduct.php?prodid=MY-311-CS&groupid=701&catid=8&subcat=1517
the hard disk is upto £63, me and others would suggest
http://www.overclockers.co.uk/showproduct.php?prodid=HD-082-SA&groupid=1657&catid=1660&subcat=1665
not sure how much extra performance the sata 3 of the segate gives over the sata 2 in 'real life' use. either way the price of both is the same so just pick one or the other. or if you have external hard disk/nas/etc for storage you could get 500gb to save some money, the 500gb seagate is £48
casewise you could drop it to the shinobi if you wanted to save money(or if due to the price increases elsewhere the budget is being stretched).
psu have a look at
http://forums.overclockers.co.uk/showthread.php?t=18332109
not modular tho its very cheap(not sure exactly how chearful but ace modder seems to think its good for the price)
I can't be bothered to total it up
p.s. stulid has been suspended so don't expect to hear from him at the moment, not sure how long the suspension is.