OK sounds better
Start SaX2 with the option -r
This will create a new XF86config file and starts SuSEs X configure program. Make shure SaX2 finds the correct Monitor or go to the property pane of the monitor and edit the sync settings.
Save and restart. After that start Yast2 and do the same
Should help, otherwise you have to edit XF86Config by hand
Dirk