Hi!
I have a pc with an old Geforce 6800 card and I have managed to successfully install the 32bit Nvidia 304.137 driver for it on Lubuntu 18.04; all thanks to a community patch. Here is the procedure.
Install build tools
$ sudo apt install gcc make build-essential gcc-multilib dkms mesa-utils
Download driver from https://www.nvidia.com/Download/driverResults.aspx/123708/en-us
Download patch from https://adufray.com/nvidia-304.137-bionic-18.04.patch
Extract archive, place patch into extracted folder and apply patch
$ ./NVIDIA-Linux-x86_64-304.137.run -x
$ cd ./NVIDIA-Linux-x86_64-304.137
$ patch -p1 < nvidia-304.137-bionic-18.04.patch
Disable nouveau driver and reboot
$ sudo -i
# cat << END > /etc/modprobe.d/disable-nouveau.conf
blacklist nouveau
blacklist vga16fb
blacklist rivafb
blacklist nvidiafb
blacklist rivatv
blacklist amd76_edac
options nouveau modeset=0
END
# update-initramfs -u
# reboot
Stop x-server
Logout
Bring up terminal with Ctrl-Alt-F1, login
$ sudo -i
# service lightdm stop
# init 3
Install NVidia driver
Ignore the first warning about preinstall failing, agree to driver recompilation on kernel update and to configuration files update. Reboot.
# ./nvidia-installer
# reboot
Driver should be working now. Check with the following:
$ lshw -c video 2>&1 | grep driver
Should output"configuration: driver=nvidia"
There is one small problem though. Apparently Nvidia driver installs it’s own version of libvdpau, which does not work with mplayer. That’s why we need to forcefully reinstall libvdpau (and possibly need to do this on kernel update, because driver will recompile and reinstall it’s own, non-functioning version for this library?)
$ sudo apt --reinstall install libvdpau1