hi there, i have a 2.8 uni mbp that i just upgraded with 6g of ram. however, my system doesn't seem to use all of it. using activity monitor, i see that my system has 3.93g free. i know that my system is capable of utilizing the ram because when i stressed the system, all 6g are capable of being used. it seems like a waste to have all that ram being free. is there something i can do to have my system use ram more?