help choosing graphics card.......

well hello guys i need ur help


budget?
max 3k..

use ?
blu ray movies ... hd stuff etc... casual gaming...

gaming ?
some light gaming cod series , nfs carbon ( at high settings @ 1024*768 res)

prefered brand ?
ati / nvdia....

any choice ?
hd 6450 , gt 520 , hd 4650 ( interested in this one but lack of availability )

any recommendations will help ...