Well after reinstalling twice this is what I found:
1) Regardless what driver I use, I could not get the internal Realtek NIC to work.
2) A clean install of RH9 has the Netgear NIC enabled. Installing NVIDIA_nforce-1.0-0261.rh90up_2.4.20_9.athlon.rpm still has it enabled. The moment I force install the driver for the MOBO NIC, it shows the Netgear as nvnet which is incorrect.
This is the link and the relevant paragraph about SPDIF for the /etc/modules.conf:
The "spdif_status" module parameter is used to enable or disable S/PDIF support in the driver. By default S/PDIF is enabled, but can be disabled by setting spdif_status to 0. The driver can only support 48kHz sample rate when S/PDIF is enabled, so disabling it will increase compatability with applications that make assumptions about what sample rates the driver supports.
Let me know how it goes.