X crashes on logout or user switching

[Peter Waller]

If I try to logout or switch to another user, I am frequently presented with a VT with a blinking cursor. It seems to be about a 50% chance that it will work and do the right thing, and a 50% chance that X dies.

I'm on 13.10 saucy daily, 64 bit.

dmesg says the following, too, but I haven't found anything else of relevance.

[822.442437] HDMI: invalid ELD data byte 68

[Peter Waller (peter.waller)]

After X crashes, if I try to restart it, frequently the screen locks up entirely. I've discovered more information in the Xorg.1.log (attached).

Here is an extract:

[ 40345.063] (II) NVIDIA(0): NVIDIA GPU GeForce GTX 560 Ti (GF114) at PCI:1:0:0 (GPU-0)
[ 40345.063] (--) NVIDIA(0): Memory: 1048576 kBytes
[ 40345.063] (--) NVIDIA(0): VideoBIOS: 70.24.21.00.02
[ 40345.063] (II) NVIDIA(0): Detected PCI Express Link width: 16X
[ 40345.067] (EE) NVIDIA(GPU-0): EVO Push buffer channel allocation failed
[ 40345.067] (EE) *** Aborting ***
[ 40345.067] (EE) NVIDIA(GPU-0): Failed to allocate EVO core DMA push buffer
[ 40345.067] (EE) *** Aborting ***
[ 40345.067] (EE) NVIDIA(0): Failing initialization of X screen 0
[ 40345.070] (II) UnloadModule: "nvidia"
[ 40345.071] (II) UnloadSubModule: "shadow"
[ 40345.071] (II) UnloadSubModule: "wfb"
[ 40345.071] (II) UnloadSubModule: "fb"
[ 40345.071] (EE) Screen(s) found, but none have a usable configuration.
[ 40345.071] (EE)
Fatal server error:
[ 40345.071] (EE) no screens found(EE)
[ 40345.071] (EE)