If your power supply has a 6-pin connector, then get an HD 6770. If it doesn't have one, get HD 7750 as it does not require one.
Just make sure its the 7750 & not the "other 7750":
http://www.engadget.com/2012/06/04/amd-radeon-hd-7750-900Mhz/
I do not know why AMD did this & did not rename the card. It makes our previous simple recommendation to have a caveat.
guys...i have the same mobo...!!
its pcie 1.0..and cards like 7750 n 7770 requires pcie 3.0...will 7770 work with g31ms2l(pcie 1.0). I mean is it compatible with mobo...m totally confused..i plannin to buy 7770, but m concerned about compatibilty.
What shd i do...if not 7770 then which card shd i buy...???
thanks