your ram will do 500mhz at 5.4.4.9,so why have you got it at 5.5.5.15 at only 480mhz? surely it will run that 480mhz at slightly lower timings.

on my p5b-d,my 6300 will do 3.5ghz(500fsb) with vcore at 1.4 with ram at 1000 1:1.your ram is rated for 500 anyway,so why not give it a try? temps at that are about 40-41c idle and about 61-63maxxed with a freezer 7 pro.