the 2500 is a 13% performance increase clock for clock, has vastly better multithreading (of course) and can encrypt disks. Not sure it would be enough to run the games that would make the multi threading worth while though.
honestly I'm not sure. If you could find another $30 or so, you could buy an FX 6200 and a lower end but clockable mobo like a GA-78LMT-USB3
and get something you can overclock. The 6200 starts off with much slower single thread, But if you can get it above 4.5 you should get that back plus a bit.
That might be enough to get you into some heavier games, but even then I'm not positive. Could be throwing good money after bad