gdm cannot get to login screen
We have been happily using VNC to access our CentOS 5.4 machine for a few months now. Today, when I tried to VNC in expecting the usual login prompt, only a mouse cursor showed up. My colleague, who has already logged on earlier in the day, had no problem using VNC, until he restarted the session and got the same problem as me. I went directly to the machine, and it also worked fine until I logged out and log back in. I got the same issue of having only a black background and a mouse cursor with the pointer and the blue circle rotating continuously (it's processing something).
I can still access the console via SSH. I couldn't find anything unusual in the /var/log/messages. I looked at /var/log/Xorg.0.log but it does not show any (EE).
I have tried rebooting normally, and everything started up fine until just before the login screen. I also tried rebooting into console mode and starting X (I tried both /usr/sbin/gdm and startx; the startx gave me the CentOS background instead of full black, but still no login screen), and reinstalling gdm. I am using an NVIDIA Quadro NVS 290 card and I heard that proprietary drivers are usually a problem, so I manually downloaded and installed the latest video driver. All gave the same result (except for startx as mentioned).
Are there any other logs I should look at? Anything else I can try? Any help would be greatly appreciated! Thanks!