NVIDIA driver not working

Installed 11.1 from DVD today, then the NVDIA driver using 1-click. Following the instructions on the website using sax2 just produced a black screen, so I rebooted and used “nvidia-settings” from the terminal (remembered that 11.0 had taught me to avoid sax like the plague) - dual monitor setup, 2 xscreens with xinerama on, hoping to rotate one screen later by adding things to xconf. Saved nvidia-settings changes to xconf and restarted X, only to be dumped into a text login.
Is this something to do with KDE 4.1 and the NVIDIA driver? Or with Xorg? What can I do about it?

Just to add to this: I had pretty much the same problem in my (brief) trials with Ubuntu 8.10 and Mandriva 2009, so I suspect it’s something to do with the NVIDIA driber 177.xx (the one installed by 1-click) not working with the new Xorg.conf. Should I try the 180.xx beta?

I just added the Nvidia repository and installed the nvidia packages using the software manager. This installs version 178.82. I had no problems. However, I would recommend installing the latest beta driver. You can dowload it from the Nvidia website and install it manually. Make sure you have the kernel-source package installed.
The beta driver runs much better with kde4 then the latest stable release.