I have created a build that will not allow you to OC the processor, but a 2300 will be able to keep up with any graphics card you throw at it right now. I also put in a different cooler, you don't really need it. but it will be quieter than the stock one.
£900.04 on the dot. Man you can get a really killer system for that budget.
Bare in mind that a lot of these prices exclude VAT so unless you've got a way of not paying VAT or claiming it back, the final price of your build will be 20% higher.