to run xorgconfig we need your horizontal and vertical rates....yes I know you have posted them above but I wanted a app to confirm it....which is what the mon* apps were.
does not help but gives other good info
so we press ahead with your specs
1) open a terminal type command
lspci > /home/yourname/pci
use this to check some of your hw that may be required if you need it in the next section
follow the prompts to enter selections that are compat with your system.....note that it will not overwrite your /etc/X11/xorg.conf until you get to the end so you exit at any time b4 that point.
when you get to video you are selecting 11 to enter your own rates pls
I hope it works
and you will have a 2d never 3d effect so am not recommending ati proprietery driver