I just had another crash.

The last lines in the kern.log before the restart were:

Dec 28 18:11:14 obiwan kernel: [28453.648355] dell-wmi: Received unknown WMI event (0x11)
Dec 28 20:14:36 obiwan kernel: [35843.150921] dell-wmi: Received unknown WMI event (0x11)
Dec 28 20:43:51 obiwan kernel: [37595.833980] dell-wmi: Received unknown WMI event (0x11)
Dec 28 21:12:38 obiwan kernel: [39319.716735] NVRM: Xid (0001:00): 6, PE0003
Dec 28 21:14:48 obiwan kernel: [39449.831650] NVRM: Xid (0001:00): 6, PE0001
Dec 28 21:14:56 obiwan kernel: [39457.838446] NVRM: Xid (0001:00): 6, PE0001
Dec 28 21:14:57 obiwan kernel: [39458.944552] dell-wmi: Received unknown WMI event (0x11)
Dec 28 21:15:03 obiwan kernel: [39460.624556] NVRM: Xid (0001:00): 6, PE007e
Dec 28 21:15:03 obiwan kernel: [39460.626992] NVRM: Xid (0001:00): 6, PE007e
Dec 28 21:15:03 obiwan kernel: [39460.629315] NVRM: Xid (0001:00): 6, PE007e
Dec 28 21:15:03 obiwan kernel: [39460.631649] NVRM: Xid (0001:00): 6, PE007e
Dec 28 21:15:03 obiwan kernel: [39460.633939] NVRM: Xid (0001:00): 6, PE007e
Dec 28 21:15:03 obiwan kernel: [39462.632943] NVRM: os_schedule: Attempted to yield the CPU while in atomic or interrupt context
Dec 28 21:15:03 obiwan kernel: [39464.629645] NVRM: os_schedule: Attempted to yield the CPU while in atomic or interrupt context
Dec 28 21:15:43 obiwan kernel: [39504.519426] dell-wmi: Received unknown WMI event (0x11)
Dec 28 21:15:44 obiwan kernel: [39505.112253] mtrr: base(0xf3000000) is not aligned on a size(0xe00000) boundary
Dec 28 21:16:16 obiwan kernel: [39537.790124] mtrr: no MTRR for f3000000,e00000 found
Dec 28 21:17:33 obiwan kernel: Kernel logging (proc) stopped.

And the deamon.log (the last entry before those lines were over ten hours ago, i.e. irrelevant):
Dec 28 21:14:59 obiwan kdm[1310]: X server for display :0 terminated unexpectedly
Dec 28 21:14:59 obiwan acpid: client 1338[0:0] has disconnected
Dec 28 21:14:59 obiwan acpid: client 1338[0:0] has disconnected
Dec 28 21:14:59 obiwan acpid: client connected from 8827[0:0]
Dec 28 21:14:59 obiwan acpid: 1 client rule loaded
Dec 28 21:15:19 obiwan kdm[1310]: X server startup timeout, terminating
Dec 28 21:15:39 obiwan kdm[1310]: X server termination timeout, killing
Dec 28 21:15:43 obiwan kdm[1310]: Failed to start X server. Starting failsafe X server.
Dec 28 21:15:43 obiwan acpid: client 8827[0:0] has disconnected
Dec 28 21:15:43 obiwan acpid: client connected from 8852[0:0]
Dec 28 21:15:43 obiwan acpid: 1 client rule loaded
Dec 28 21:16:17 obiwan acpid: client 8852[0:0] has disconnected
Dec 28 21:16:17 obiwan acpid: client connected from 8882[0:0]
Dec 28 21:16:17 obiwan acpid: 1 client rule loaded
Dec 28 21:16:37 obiwan kdm[1310]: X server startup timeout, terminating
Dec 28 21:16:57 obiwan kdm[1310]: X server termination timeout, killing
Dec 28 21:17:07 obiwan kdm[1310]: X server is stuck in D state; leaving it alone
Dec 28 21:17:07 obiwan kdm[1310]: Failed to start X server. Starting failsafe X server.
Dec 28 21:17:33 obiwan acpid: client 8882[0:0] has disconnected
Dec 28 21:17:33 obiwan acpid: client connected from 8915[0:0]
Dec 28 21:17:33 obiwan acpid: 1 client rule loaded


Due to the X server restart I don't have any informations about the crash itself left :(

Are those informations sufficient to figure out what the problem is? What other informations are required?