ideally you should ask for this drivers to be added to the repos
this command i will write will make the installation unsupported but it seems that you need to do it so here it goes
i will suppose that you are using kde4 so open the folder where you have the file you downloaded(open home or dolphin), in there press the F4 key to load on dolphin a console
in that console write rpm -i theexactnameofthepackageyoudownloaded.rpm and enter(replace theexactname with the real name of the package, upercase if exist should be used when required)
the rpm should be installed and working
if it requires another package it will tell you which one and stop the install process so you will have to verify in synaptic that you are completely updated and if a library is required search it there, install it and try again
btw welcome to the forum