At this time in /var/log/kdm.log I see: Backtrace: 0: /usr/bin/X(xorg_backtrace+0x26) [0x4f1b66] 1: /usr/bin/X(xf86SigHandler+0x41) [0x485a61] 2: /lib/libc.so.6 [0x7f0f70b36040] 3: /usr/bin/X [0x4b77f7] 4: /usr/bin/X [0x4b7b95] 5: /usr/bin/X(xf86Wakeup+0x46d) [0x48629d] 6: /usr/bin/X(WakeupHandler+0x4b) [0x451e6b] 7: /usr/bin/X(WaitForSomething+0x1ef) [0x4ef5ef] 8: /usr/bin/X(Dispatch+0x80) [0x44e020] 9: /usr/bin/X(main+0x3bd) [0x433d8d] 10: /lib/libc.so.6(__libc_start_main+0xe6) [0x7f0f70b215a6] 11: /usr/bin/X [0x433219] Saw signal 11. Server aborting. ddxSigGiveUp: Closing log ddxSigGiveUp: re-raising 11