if you want to go i7 you will HAVE to get new ram, motherboard, and cpu. cheaped i7 cpu is ~300 usd the motherboards are at LEAST 175 usd and the ram is gonna be ~100 usd. if you don't have a tight budget go for it. if not go for a socket AM3 motherboard (which can be had for ~110) and a lot of them can use your old ddr2 ram and a Phenom II X4 940 can be had for 180 usd. good choice on a budget in my opinion. though if money is not a problem go i7.