hey people, I am planning a new upgrade which will commence roughly straight after crimbo

so i would have sold my mighty socket 939 and will be going for a ludicrously overclockable conroe set up

i shall have £600 from my bits and plus some pay which will be £300

so £900 and on top of that i shall allready have my graphics card and Powersupply, hard drive, and monitor, mouse, keyboard, case.

so £900 to spend on mem cpu mobo another gfx card?

i need some help

what should i get