|" go to a newer and better sys."|
Third generation Core i7 really smokes the numbers if you believe the numbers.
There are only a few instances where you get more cpu for the money ratio when doing only a cpu upgrade.
Most cpu's are sold almost at the same rate. High end systems cost same per performance dollar.
I would suggest against an upgrade of only your cpu. Generally you don't get much performance increase for the money.
When you go to a new motherboard you may see increases in ram and true, you may have to buy new ram and maybe even power supply.