I have exactly the same problem.
I recently upgraded to RH 7.3 (default is 2.4.18-3 kernel) and reinstalled the nvidia drivers (2960 for Athlon) from rpm. That worked fine (much easier than when I first did this on RH 7.0).
I then upgraded the kernel to 2.4.18-5 from rpm and the nvidia drivers no longer worked. The nv driver works, but I can't be bothered to sort out the acceleration for it.
Luckily I didn't delete the old kernel so I'm using that.
This suggests it's not an install problem but a kernel module problem.
I'm hoping this will get fixed in the next kernel release or driver release.