Nvidia Update in 9.1

It seems the Nvidia update works best if you update the kernel with YOU first reboot and then perform a YOU update with NVIDIA. If i run all updates at once including NVIDIA I get a freq. over-run, I cannot start SAX2 in init3 because of same error. If I edit XF86Config with proper settings. Monitor (in this case Viewsonic VP171 crt) is out of focus. I can't find much consistancy on installs of 9.1 on the same hardware. I have 3 boxes. Installs still seem unpredictable, though zeroing my hard disk seemed to work. Just wondering if anyone else had this problem. My system Soyo kt400 ultra Athlon XP 1.8, Seagate 160 GB. Nvidia 420