ok i got a question lets say i wanna purchase an X850XT
then i decide i wanna do crossfire, i have a crossfire mobo do i need to replac emy X850 with a crosfire supported vid card or can i just a crossfire supported card next to my X950XT?
No can only crossfire cards of the same generation so:
x850 with and x850
or
X1600 with an x1600
You can use cards of the same generation with different speeds togehter.
Also the x1600 and x1300 do not need crossfire master cards you can use 2 plain cards together and they will work as crossfire(no external cable is needed).