Just a thought, perhaps you could get hold of a LiveCD, PCLinuxOS, Knoppix, Mepis, etc, and run it. It should autodetect everything. (PCLOS comes with an ATi-specific version though you may wish to try it "both ways").
If you get a good graphics screen, print out or write down the section of the file /etc/X11/xorg.conf (it could be called XF86Config or XF86Config-4 as well) which refers to your graphics driver. Also in the "Monitor" section, write down the numbers on the lines "HorizSync" and "VertRefresh". This file will have been built "on-the-fly" by the liveCD, and will vanish as soon as you close down.
Now run your SuSE setup again, and edit the file (one of the above three names) and see how the same section compares. Not promising anything, but you may get a "lead" from that. Maybe amend the file to that of your liveCD setup if that worked better. The only bit you must NOT change is the "Identifier". Also see if the HorizSync and VertRefresh numbers are different maybe alter them as well.
Not promising anything, but since you've had no reply for 2 days, it might just work.
Of course, if any of these live CDs work, and you cannot get SuSE going, they can each be installed instead, Mepis and Knoppix can use Debian repositories for upgrades, PCLinuxOS has its own repositories (but visit the web site as the address has changed so you'll have to update it). PCLOS and Mepis are friendly distros, see "Mrs Devnet's Experiment" in "Discussion" section.