For cooling alone..He works for supercomputer cooling..pretty lucky, but did he spend 30K on just the nitrous cooling?
anyways pkhamidar2com, since you have a total budget of £450, think a i5-2500 could fit in there it is really up to you, the difference beetween the 2300/2400/2500/k depends mostly on budget (and whether or not you want to OC).