What I have: Fresh installed Pinstripe GNOME workstation, Rage128 video card. What happens: 1. boot it. 2. startx - everything OK 3. close X session. No matter how - throug menu or ctrl-alt-backspace. 4. startx again - black screen and nothing more. No reply ctrl-alt-backspace, no ctrl-alt-f1 etc, but ctrl-alt-del caused reboot. What's that? r128 driver trouble again?
Make sure you have the agpgart module loaded before starting X the first time. It's the r128 kernel DRM driver oopsing. This has been fixed in a later kernel build.