Hi Bob,
This is something I'm working with right now.
Like you, I like using AMD systems. And because in the real world things don't stand still just because some Linux distros can't keep up, we have this frustrating problem about having problems with running them on current (and very often common) hardware.
As SME 6x is not at production level yet, I cannot roll out any production servers using 6x. Therefore, I had to manually upgrade the kernel of a fresh SME 5.6U4 server to the latest RH 7.3 errata kernel (version 2.4.20-20.7 at the time). This fixes up the issue with support for the VIA 8235.
Be warned though, contrary to some people's opinion, upgrading the kernel *can* affect some contribs that you may need to add in to your SME. One important example is the Freeswan contrib which I need to get going desparately and have used before on stock systems. Once you deviate from stock systems, very often, you are on your own for many, many things. Most times people won't or can't help you if you are no longer using a standard system (kinda ironic because we often gripe about SME using RH kernels different from the normal distro versions, yet when we are forced to do the same, we are still on our own !! There are patches for the normal RH kernels but you will be hard pressed to find patches for the errata kernels.)
Kelvin