ubuntu developers updated the repository of nvidia-glx from 9631 to version 9755, this cut off support for card's older than FX series (f.e. geforce 3,4).
those users should use nvidia-glx-legacy (7xxx) from now on, instead of legacy 9631, which is not available in the repos. (and i doubt this is a good driver for a geforce 4)
so i tried to install 9631 from nvidia.com but somehow its not working (kernel is 2.6.20-13 generic), (all requirements like build essential are given)
in the irc channel #ubuntu-kernel i was told that the old 9631 driver from the repos was patched somehow to work with the -12 kernel.
at the moment im not able to get any direct rendering, i wasnt able to install nvidia-glx-legacy (but it seems that is just me). on the top of it all the "nv" opensource driver is broken too at the moment -> i cant even use the tv-out
id be glad if someone could give me information, how to get 9631 driver work, or any other solution.
also several threads on ubuntuforums:
edit: i got 9631 working now, but only with this in xorg.conf
Option "Composite" "Disable"