Hi there, see it isn't a problem, Backtrack doesn't have the drivers by default and it don't have the app called Hardware Drivers, ok, in first instance don't try to download it it won't work, you need install the drivers manually, also u need install the APP SDK from AMD, luckyly you can find the how to in the Back-Track wiki, I will leave the link over here:
http://www.backtrack-linux.org/wiki/...Install_OpenCL
It works perfectly over R1/R2 and the normal version xD.
I use AMD 6480 and this makes my GPU give me an awesome Desktop

have Fun