Can't help much except to say that the 3123 driver is working great for me on my Red Hat 7.3 system. I would recommend removing both the GLX and kernel packages and re-installing, as opposed to the upgrade you attempted.
I would shutdown X first, with
Then remove the drivers with
rpm -e NVIDIA_GLX NVIDIA_kernel
Then install them again with
rpm -ivh NVIDIA_GLX*rpm NVIDIA_kernel*.rpm
Cross your fingers and restart X with