How to display a single dual-function card

My card is ASUS's EAH2400PRO MG/HTP/256M
play Call of Duty 4, effects on the closed half (555 ~ ~)
“ I would like to buy a piece like the two together with significant double ~ ~
Run the information I have seen a ~ ~
told me that as long as the same kind of brand are compatible???
Not those technical words ~ ~ (long and smelly)
personal opinion ~ ~
satisfied, then points to another! ! ! !

dual graphics card than to support (usually two to do the same two-card) to support the main board of the most important
to look up your motherboard can double your graphics card is like after the election