Have you ever run the Red Hat Linux graphical installer only to find that X won't start when the install is complete? How did X run during the graphical install and fail later?

The Anaconda installer detects the hardware during the installation and writes a temporary XF86Config file which it uses to provide the install GUI. You can find this temporary file during the second stage of the install and copy it to a place that you can find it when the installer completes. Then just move that copy to the final destination and X will run with the same parameters as it did during the install process.