I had similar problems w/ GeForce DDR (Score 2)

Listen to the kernel advice above, and when you have that accomplished, forget about the RPMS that install GLX and the NVIDIA kernel module. Grab the tarballs off the same NVIDIA page you found the RPMS at (they're the last links on the page) and follow the make directions in NVIDIA's FAQ - it's not hard at all. Make very sure you clean out the MESA files they tell you to - they're not kidding. Now that you have the kernel module and GLX stuff, fire up X. This is where I have MY problems. If I run a default monitor (specify NO HFreq or VFreq info in XF86Config) it runs like a champ. If I put the same monitor info that worked in the old version of XFree86 (the correct capabilities of my monitor), the NVIDIA driver tries to set my resolution at something insane like 1836x1543 90hz and bails out. The bizarre thing is that the logs tell me that the NVIDIA driver sees the correct monitor info, says it's using it, but seems to ignore it anyway. There's a strange space in the log where it says "Using 35.00 -86.00hz" where the other line says "Using 50.00-130.00". No space before the hyphen in the second one. Don't know if that's related, but it can't hurt. Good luck!!!