since you had mention fglrxconfig. I assume that you had download the lastest driver from http://www.schneider-digital.de/html/download_ati.html
and your rh9 was running the lastest X4.3.0.
Just install it again and do "rpm -ivh <package's name>" if it says something it's wrong with dependencies problem. then do "rpm -i --force <package's name>"
after you installed the proper driver. just do "fglrxconfig" as it told you. That script works great. then restart. go use System Log or "glxgears" to check weather your card it's running. if the glxgears util runnings around 3000 to 4000, then your driver it's working. If it did say something about "fail to initialize modules driver or ...." do fglrxconfig again and use external agpgart. then add "/sbin/modprobe agpgart" and "/sbin/modprobe fglrx" to your /etc/rc.local file.
then restart and see what it says.
I bet one of the step must work for you.
Also, what motherboard are u using??