nvidia legacy driver and nvidia-glx questions
 

After nearly half a year of not properly reading my log file I found out that my nvidia card isn't supported anymore. The nvidia site says that I can use the legacy driver however I can't find a download for that. I'm using the nv driver now in my XF86Config and it's working so is that the mentioned driver?

Would it be good to move to the nvidia-glx open source driver or doesn't this add anything special?

No, nv is the one in XFree86. The one from nVidia is called nvidia in the configuration file.
What card is it (give us output from lspci or lspci -v)

There are some packages in un-free and contrib that helps installing nVidias binary drivers for those cards. Read my posting some where here where I show how to do it in an easy way for Debian.

/Yours

As I said, my card isn't supported anymore by the nvidia driver. It's too old or so ;)

I found it out. nv only has 2D stuff. The nvidia-glx and nvidia-kernel-source fixed the problem as it has glx support.

So that no one get's it wrong.
You still have 3D, but not hardware support for it, when you use nv from XFree86 instead of nvida from nVidia. But the 3D is emulated in software by mesa-packages. It's nothing to run demanding graphical games with...

The nv driver didn't work for neverwinter nights. It gave the error that the glx module wasn't found. Though nvidia doesn't support my card anymore with the official driver I can use the nvidia-glx package. So now I use the nvidia driver again :)

If I havn't forgot something, Glx-module in nvidias is GLcore in nv, and is provided by mesa.
But anyway, if you want more than 5 frames per second, you need nvidia.

This is what you need to set up when you configure xserver-xfree86
(The window where you select XFree86 server modules)

dpkg-reconfigure -plow xserver-xfree86

If you have a set up that works with nv, don't touch anything else the window where you chose which video card driver you want to use AND the window where you choose which OpenGL-drivers (in server module window).

nv => GLcore and dri modules (and NOT glx)
nvidia => glx (and NOT GLcore and dri)

This should give you a working OpenGL set up. One hardware optimised from nVidia (nvidia) and one software driver from XFree86 (nv).