I agree with above, but that being said if you are at 7 out of 8 that's pushing it, not leaving much wiggle room for background processes etc. Unless you are running a very, very consistent workload your memory usage will go up and down as different processes start and finish, background tasks open and close, etc. I know memory is expensive right now, but if you can swing it an upgrade to 16gb is becoming "standard" these days.