If you are buying new pc better consider this:
Intel's New Core i7 and Core i5 Processors Explained
Intel's New 'Jasper Forest' Chip Improves Performance With Less Power
I say, budget wise, stick with your core 2 quad processors. It can still run well the demanding applications and games nowadays. i7 and i5 processors are not yet in there very true form... better wait to unleash everything...
bow...