don't get the phenom, defiantly get one of the intel cpu's. the core 2 quad is still a good gaming processor, so if you buy a 15 now, you'll be good for at least another 5 years. i'd recommend the 3570k, as it uses less power at full load and is unlocked. overclocked, nothing can make an i5 sweat. the phenoim is ok, but gets beat by the i5 in every scenario, and will pull more power to boot. trust me, intel is worth the money.
to back this up, ihave used both the phenom x4 965 and the 3570k, and i can tell you that the i5 is way better.