then that person is retarded, you will not use any performance, if you buy a cpu with 6mb l3, then all 6 megs will be available, with am2+ boards, the only thing that changes is that you use ddr2 instead of ddr3, in the case of an am2 board that extends support for am3, then you will be limited to 2000mt/s on the hyper transport, either way there will be no significant decrease of performance.