I have athlon 64 x2 4000 with 4 gigs ddr2 ram and a nvidia 8600 gt 512mb and windows vista, should i get a ati 5770 1gig or get new mob with phenomII x3 720? i can only do one or the other right now ? I am currently PLaying BAttlefield Bad Company 2. What would be best option to improve my fps ?