mobo won't show up in system info.

AMD phenom II x6 1090t
8 gigs of ram
radeon hd 5770 (had a 5850 but it never worked so i used an 5770 one.)
budget 200-300 USD max
the question is if I upgrade how much would a new graphics card benfit this pc and what price point/graphics card would maximize benefit the most? (for the money/pc.)
my goal is to be able to stream/fraps coh2 and other games (not necessarily max graphics) and hopefully be able to run coh2 at higher than low/minimum settings