i have ubuntu 8.04 and i have 3 kernels installed: generic, rtai and multimedia. on the generic kerne, the 3d nvidia driver works fine, but on the other kernels it refuses to work, working in low res mode with the vesa driver. does anyone know of a solution where the 3d driver will work on all/any kernels on my box. thanks in advance

james waples,14

Go to the Nvidia site and download the driver. Run the installer. Done.

This does require you to have the gnu compiler environment, and the proper set of kernel headers, available.

well the nvidia installer compiles the kernel module against whatever is in '/usr/src/linux' every time I change or recompile my kernel I have to reinstall the nvidia driver to get it to work. while it is possible to have separate modules for each kernel; I don't know how you would make this work for the nvidia driver as there is a module for x11 as well. just curious what is the reason you have 3 kernels? why can't you have 1 that does everything you need?

This is not specifically true. It doesn't matter where the source for the running kernel is; it can be on a different drive or even an NFS drive. The nvidia driver look at /lib/modules/`uname -r`/source to find the source for the currently running kernel.

Yes, this will happen. The problem, I suspect, is in the compilation of the libraries in /usr/lib/.

What you need to do is compile these libraries in each kernel, then uniquely name them, then symlink them to the required standard name. You alter the startup scripts so that, before starting X after booting, you determine what kernel is running and create the proper symlink for the libraries that work with that kernel.

You specifically want to look at libGL.so and libGLcore.so in /usr/lib.

thanks. rather confusing as im a relative newbie and i cant be bothered to recompile my kernel cos it would probably break it

and to steve johnson: i have one that is normal, one (rtai) for linucnc/emc for my homebrew cnc machine and one for music making

OK, I used to have to switch kernels like that for making music because I never could get the nvidia driver to play nice with the low latency kernel stuff. now I just have a dedicated box for audio recording with no monitor. when I did switch kernels like that I realized that I only needed the 'nvidia' driver when I was playing games not when I was recording. what I did was have the nvidia driver properly installed for the regular kernel and two xorg.conf files:

xorg.conf.nvidia --> set up to use the 'nvidia' driver.

xorg.conf.vesa --> set up to use the 'vesa' driver.

Then I wrote a script that used 'uname' to determine what kernel I was running and copy the required file to '/etc/X11/xorg.conf' I set this script up to run at boot before X started. The result was if I selected my regular kernel from grub it copied xorg.conf.nvidia to xorg.conf and I had full 3D for games and such, but if I selected my low latency kernel from the grub menu it copied xorg.conf.vesa to xorg.conf and started X with the 'vesa' driver. If you are interested post the output of 'uname -a' for each of the 3 kernels. I can dig out that script and adapt it for your system.

Unrelated, but I would like to hear about your cnc. I've been thinking about building one for a while and I'd like to know what hardware/software you used to get it to work on linux.

to steve: my email address is jamwaffles@googlemail.com. please feel free to ask any questions on there and ill try and help. thanks for the solution

james

If I am not mistaken there is a way to have nvidia modules compiled for multiple kernels so that you simple can boot the kernel you prefer and the appropriate nvidia kernel is loaded. Just like all other modules which are specifically compiled for one kernel.

Open the NVIDIA...nnn...RUN file you downloaded with a text editor, and read thru the first part. It is a text file. I gives directions how to use it for different kernels. I haven't tried it yet, I was up to do it, but at the time the installer was not compatible with my kernel so I postponed it.

jlinkels

thanks very much. i think i may have sorted the problem anyway, but if it breaks again (probably), ill have a look at your solution. thanks very much

james

Thank you for the info on your cnc. I actually had the 3 steppers and drawer slides all ready set aside for a machine like yours. what are you using as a cutting tool? what are you cutting?