also, if that is a 3k (in US dollar), i would suggest that you do A LOT of reading (and watching) tutorials, the last thing you would want is to ruin that rig of yours. besides, if you have that kind of rig, it should be fast, right?
if you really want to go at it, well it is your choice, and i will still say that you read read and read. Overclocking is not a 5 minute task, do it wrong and it will cost you. besides, its too long to type everything here while there are tons of guides readily available online