Report the problem to RedHat. If it is a bug and they release a patch you can use it in the form of an update disk, for example:
Also, have you tried all the possible install modes, including low-res and text modes?
I had 2 S3 cards that were working fine with RH6.x, and when 7.x came along, blammo. It would be nice if newer versions didn't have these kinds of problems...