I will include my Xorg.0.log and Xorg.0.log.old, but are these the appropriate files for this issue?  I was under the impression that gdm had its own set of log files (/var/log/gdm) and separate x invocation.

Also, I'm not sure if I have one, two, three, or four related issues here.  I will enumerate as best I can what I am seeing to make things clearer:


1)  The gdm crash restart loop:  The animated "Ubuntu" splash screen (via xsplash, I think) comes up, spins for a few seconds, makes the bongo startup sound, goes dark for a moment, and then the process repeats, indefinitely.  Something like the following appears in /var/log/syslog during this time:

Nov  3 11:29:22 exachron gdm-simple-slave[2550]: WARNING: Child process -2586 was already dead.
Nov  3 11:29:22 exachron gdm-simple-slave[2550]: WARNING: Unable to kill D-Bus daemon
Nov  3 11:29:32 exachron gdm-simple-slave[2625]: WARNING: Child process -2661 was already dead.
Nov  3 11:29:32 exachron gdm-simple-slave[2625]: WARNING: Unable to kill D-Bus daemon
Nov  3 11:29:43 exachron gdm-simple-slave[2694]: WARNING: Child process -2729 was already dead.
Nov  3 11:29:43 exachron gdm-simple-slave[2694]: WARNING: Unable to kill D-Bus daemon
Nov  3 11:29:53 exachron gdm-simple-slave[2764]: WARNING: Child process -2800 was already dead.
Nov  3 11:29:53 exachron gdm-simple-slave[2764]: WARNING: Unable to kill D-Bus daemon
Nov  3 11:30:03 exachron gdm-simple-slave[2834]: WARNING: Child process -2870 was already dead.
Nov  3 11:30:03 exachron gdm-simple-slave[2834]: WARNING: Unable to kill D-Bus daemon

If I use <ctrl> <alt> F1 while on the splash screen, wait a few moments, and then <ctrl> <alt> F7 (or sometime F8 or F9, I think), I am then presented with the login screen and can log into my gnome session from there.


2)  The video does not work in the text consoles (i.e. blank screens), but the login still works.  I tested this by switching to a text console (<ctrl> <alt> F1) while logged into my gnome session, blindly typing my username and password, and then 'touch'ing a non-existent file.  I then switched back to my gnome session (<ctrl> <alt> F7) and verified that the new file exists.  A further observation is that if I switch to a text console immediately upon startup (after booting) before gdm is given a chance to crash even once, the text console video works and continues to do so even after I've logged in.


3)  X crashes intermittently when I am performing certain actions in my gnome session.  Changing the desktop background will often crash it (but not always) and browsing certain webpages in firefox will crash it.  This dumps me back into the gdm restart loop, except that, about 1/2 the time, the video has become so corrupted (i.e. I move the mouse and the screen swims around) that I can no longer recover and have to reboot.


4) If I switch to a text console and switch back to gnome, the screen fonts & font colors are corrupted (I'll attach a <Print Screen>).  The corruption goes away after a redraw.


Three more observations:

1) Any action of switching between, moving or resizing windows takes an inordinate amount of time, during which the Xorg process occupies a large %CPU (according to top - anywhere from 15 to 100% for up to a few seconds sometimes).

2) I ran Ubuntu 8.04 on this same machine without any notice-able stability problems for quite some time.  It wasn't a power-house, but I had no problems with internet video, remote desktop to my upstairs machine (same LAN), or lag during window manipulation.  I switched over to 9.10 because my old hard drive ate a good chunk of my Linux partition during its death throws (I've purchased a new one), and, you know, move-with-times, right?

3) In frustration with regards to this problem, I attempted to use an alternate PCI video card to see if I'd get better support from a different driver.  I tried 5 such cards (I've got a box of them), including ATI Rage (3 flavours), Trident, and MGA, but was not able to boot past initramfs with any of them, perhaps due to something weird with my bios (I did make sure to disable the on-board graphics in the bios).  Initramfs reported (in all cases) an ext3-fs error ("Block bitmap for group 1 not in group(block 0)"), that would not allow my root to be mounted. I couldn't mount the device manually either.  Also, 60 seconds after sitting at the initramfs prompt, a low memory corruption is reported.  I did run memtest86, which found no problems with my RAM.  I was able to boot into Windows with the PCI video cards, but only able to get an in-range refresh rate for my monitor (and therefore see-able video) out of one of them (probably due to the drivers not yet being installed / configured).


I will attach (after this post) the promised screen corruption image, and the Xorg logs.  Please don't hesitate to let me know what else I can provide.  Thank you very much for looking into this issue.