Re: Debian 2.6.5 nvidia driver issues
From what I've heard Debian's apt is exceptionally good, so a simple apt-get nvidia-glx should do the trick. I don't really know though. It *is* a good idea to install this package (again). In principle the Nvidia driver is shipped with the GLX extension and supporting libraries, so you should first check whether everything was installed properly (consult the README that came with the driver).
You should really configure your kernel to use 8K stacks, instead of 4K. There are plenty of pointers on this forum about how to accomplish that. Basically, you will have to reconfigure the kernel using 'make menuconfig' for instance, recompile and install the kernel (and boot it of course). The Nvidia driver will not work (properly), when using 4K stacks. If your kernel is already configured to use 8K stacks, you don't have to do anything, of course.