To work in sli do both cards have to be the same brand

[quickster]

I have an asus gtx 550 ti, do i have to use another asus of the same model or can i use something like a galaxy gtx550 ti for both cards to work in sli mode

 

[rolli59]

Just as long as both cards are GTX550Ti with SLI connectors they will work.

 

[pro-gamer]

they should work fine with different brands but make sure models should be same.