I have a nvidia video card ... I have found a solution for play quake2 (installed in Debian-amd64- way )The nvidia readme file, talk about a libGL.so symlink , but in Debian Quake2 folder I can't found it. You can't play running a simple "quake2" but have to use "quake2 +set vid_ref glx +set sw_mode 0"
regards Antonio ------------------------