totálně chcípá grafika

Zdravím,
poslední dobou (od nějakého update?) mě občas při zapnutí PC totálně chcípne grafika - jak v GUI, tak v CLI. Ovšem vzdálené přihlášení funguje. Jde o PC s AMD APU, staré asi rok. Ve /var/log/warn se objevuje toto (pokud systém normálně naběhne, neobjeví se řádky uvozené ***):

Oct 21 19:25:23 vamad udevd[327]: RUN+="socket:..." support will be removed from a future udev release. Please remove it from: /etc/udev/rules.d/71-multipath.rules:7 and use libudev to subscribe
to events.
Oct 21 19:25:23 vamad kernel: [ 0.000000] ACPI: RSDP 00000000000f0450 00024 (v02 ALASKA)
Oct 21 19:25:23 vamad kernel: [ 0.000000] ACPI: XSDT 00000000beed9068 00054 (v01 ALASKA A M I 01072009 AMI 00010013)
Oct 21 19:25:23 vamad kernel: [ 0.000000] ACPI: FACP 00000000beedf7f8 000F4 (v04 ALASKA A M I 01072009 AMI 00010013)
Oct 21 19:25:23 vamad kernel: [ 0.000000] ACPI Warning: Optional field Pm2ControlBlock has zero address or length: 0x0000000000000000/0x1 - not using it (20120320/tbfadt-579)
Oct 21 19:25:23 vamad kernel: [ 0.000000] ACPI: DSDT 00000000beed9150 066A4 (v02 ALASKA A M I 00000000 INTL 20051117)
Oct 21 19:25:23 vamad kernel: [ 0.000000] ACPI: FACS 00000000bf15bf80 00040
Oct 21 19:25:23 vamad kernel: [ 0.000000] ACPI: APIC 00000000beedf8f0 00072 (v03 ALASKA A M I 01072009 AMI 00010013)
Oct 21 19:25:23 vamad kernel: [ 0.000000] ACPI: MCFG 00000000beedf968 0003C (v01 A M I GMCH945. 01072009 MSFT 00000097)
Oct 21 19:25:23 vamad kernel: [ 0.000000] ACPI: HPET 00000000beedf9a8 00038 (v01 ALASKA A M I 01072009 AMI 00000005)
Oct 21 19:25:23 vamad kernel: [ 0.000000] ACPI: SSDT 00000000beedf9e0 00695 (v02 AMD ALIB 00000001 MSFT 04000000)
Oct 21 19:25:23 vamad kernel: [ 0.000000] ACPI: BGRT 00000000beee0078 0003C (v00 ALASKA A M I 01072009 AMI 00010013)
Oct 21 19:25:23 vamad kernel: [ 0.000000] Zone PFN ranges:
Oct 21 19:25:23 vamad kernel: [ 0.000000] DMA 0x00000010 -> 0x00001000
Oct 21 19:25:23 vamad kernel: [ 0.000000] DMA32 0x00001000 -> 0x00100000
Oct 21 19:25:23 vamad kernel: [ 0.000000] Normal 0x00100000 -> 0x00220000
Oct 21 19:25:23 vamad kernel: [ 0.000000] Movable zone start PFN for each node
Oct 21 19:25:23 vamad kernel: [ 0.000000] Early memory PFN ranges
Oct 21 19:25:23 vamad kernel: [ 0.000000] 0: 0x00000010 -> 0x0000009d
Oct 21 19:25:23 vamad kernel: [ 0.000000] 0: 0x00000100 -> 0x000bedee
Oct 21 19:25:23 vamad kernel: [ 0.000000] 0: 0x000beed8 -> 0x000beed9
Oct 21 19:25:23 vamad kernel: [ 0.000000] 0: 0x000bf142 -> 0x000bf143
Oct 21 19:25:23 vamad kernel: [ 0.000000] 0: 0x000bf389 -> 0x000bf752
Oct 21 19:25:23 vamad kernel: [ 0.000000] 0: 0x000bfef4 -> 0x000bff00
Oct 21 19:25:23 vamad kernel: [ 0.000000] 0: 0x00100001 -> 0x00220000
Oct 21 19:25:23 vamad kernel: [ 0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total pages: 1931852
Oct 21 19:25:23 vamad kernel: [ 0.000000] Policy zone: Normal
Oct 21 19:25:23 vamad kernel: [ 0.000000] Fast TSC calibration using PIT
Oct 21 19:25:23 vamad kernel: [ 0.001000] Detected 2096.150 MHz processor.
Oct 21 19:25:23 vamad kernel: [ 0.763047] #2
Oct 21 19:25:23 vamad kernel: [ 0.816804] mtrr: your CPUs had inconsistent variable MTRR settings
Oct 21 19:25:23 vamad kernel: [ 0.820504] ACPI: Executed 1 blocks of module-level executable AML code
Oct 21 19:25:23 vamad kernel: [ 1.415704] Dquot-cache hash table entries: 512 (order 0, 4096 bytes)
Oct 21 19:25:23 vamad kernel: [ 2.720311] usb 8-1: ep 0x81 - rounding interval to 64 microframes, ep desc says 80 microframes
Oct 21 19:25:23 vamad kernel: [ 10.948072] sr0: scsi3-mmc drive: 48x/48x writer dvd-ram cd/rw xa/form2 cdda tray
Oct 21 19:25:23 vamad kernel: [ 11.100211] [Firmware Bug]: powernow-k8: No compatible ACPI _PSS objects found.
Oct 21 19:25:23 vamad kernel: [ 11.100213] [Firmware Bug]: powernow-k8: Try again with latest BIOS.
Oct 21 19:25:23 vamad kernel: [ 11.101945] [Firmware Bug]: powernow-k8: No compatible ACPI _PSS objects found.
Oct 21 19:25:23 vamad kernel: [ 11.101946] [Firmware Bug]: powernow-k8: Try again with latest BIOS.
Oct 21 19:25:23 vamad kernel: [ 19.675542] [Firmware Bug]: powernow-k8: No compatible ACPI _PSS objects found.
Oct 21 19:25:23 vamad kernel: [ 19.675543] [Firmware Bug]: powernow-k8: Try again with latest BIOS.
Oct 21 19:25:23 vamad kernel: [ 20.888864] vboxguest: VirtualBox Guest PCI device not found.
Oct 21 19:25:24 vamad kernel: [ 23.573709] vboxdrv: fAsync=0 offMin=0x38e offMax=0x145a
Oct 21 19:25:29 vamad kdm_config[739]: Multiple occurrences of key 'UseTheme' in section [X-*-Greeter] of /usr/share/kde4/config/kdm/kdmrc
Oct 21 19:25:34 vamad checkproc: checkproc: can not get session id for process 2247!
Oct 21 19:25:34 vamad ifplugd(eth0)[1205]: client: eth0 device: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 06)
Oct 21 19:25:39 vamad dhcpcd[2539]: eth0: Failed to lookup hostname via DNS: Name or service not known
*** Oct 21 19:25:45 vamad kernel: [ 45.014215] radeon 0000:00:01.0: GPU lockup CP stall for more than 10020msec
*** Oct 21 19:25:45 vamad kernel: [ 45.014224] GPU lockup (waiting for 0x00000009 last fence id 0x00000001)
*** Oct 21 19:25:45 vamad kernel: [ 45.156715] radeon 0000:00:01.0: Wait for MC idle timedout !
*** Oct 21 19:25:45 vamad kernel: [ 45.310448] radeon 0000:00:01.0: Wait for MC idle timedout !
*** Oct 21 19:25:45 vamad kernel: [ 45.462622] radeon 0000:00:01.0: Wait for MC idle timedout !
*** Oct 21 19:25:46 vamad kernel: [ 45.630581] [drm:r600_ring_test] *ERROR* radeon: ring 0 test failed (scratch(0x8500)=0xCAFEDEAD)
*** Oct 21 19:25:46 vamad kernel: [ 45.630583] [drm:evergreen_resume] *ERROR* evergreen startup failed on resume
Oct 21 19:25:52 vamad ifplugd(eth0)[1205]: client: Starting DHCP4+DHCP6 client on eth0. . . . . . . .
Oct 21 19:25:52 vamad ifplugd(eth0)[1205]: client: eth0 IP address: 192.168.0.102/24
Oct 21 19:25:52 vamad ifplugd(eth0)[1205]: client: eth0 DHCP6 continues in background
Oct 21 19:26:13 vamad pulseaudio[4620]: [pulseaudio] pid.c: Daemon already running.
Oct 21 19:26:14 vamad pulseaudio[4632]: [pulseaudio] pid.c: Daemon already running.

/var/log/messages také nevypadá zrovna hezky:
...
Oct 21 19:25:45 vamad kernel: [ 45.014215] radeon 0000:00:01.0: GPU lockup CP stall for more than 10020msec
Oct 21 19:25:45 vamad kernel: [ 45.014224] GPU lockup (waiting for 0x00000009 last fence id 0x00000001)
Oct 21 19:25:45 vamad kernel: [ 45.015344] radeon 0000:00:01.0: GPU softreset
Oct 21 19:25:45 vamad kernel: [ 45.015347] radeon 0000:00:01.0: GRBM_STATUS=0xA0003828
Oct 21 19:25:45 vamad kernel: [ 45.015349] radeon 0000:00:01.0: GRBM_STATUS_SE0=0x00000007
Oct 21 19:25:45 vamad kernel: [ 45.015351] radeon 0000:00:01.0: GRBM_STATUS_SE1=0x00000007
Oct 21 19:25:45 vamad kernel: [ 45.015353] radeon 0000:00:01.0: SRBM_STATUS=0x20020940
Oct 21 19:25:45 vamad kernel: [ 45.156715] radeon 0000:00:01.0: Wait for MC idle timedout !
Oct 21 19:25:45 vamad kernel: [ 45.156717] radeon 0000:00:01.0: GRBM_SOFT_RESET=0x00007F6B
Oct 21 19:25:45 vamad kernel: [ 45.156821] radeon 0000:00:01.0: GRBM_STATUS=0x00003828
Oct 21 19:25:45 vamad kernel: [ 45.156823] radeon 0000:00:01.0: GRBM_STATUS_SE0=0x00000007
Oct 21 19:25:45 vamad kernel: [ 45.156825] radeon 0000:00:01.0: GRBM_STATUS_SE1=0x00000007
Oct 21 19:25:45 vamad kernel: [ 45.156827] radeon 0000:00:01.0: SRBM_STATUS=0x20020940
Oct 21 19:25:45 vamad kernel: [ 45.157830] radeon 0000:00:01.0: GPU reset succeed
Oct 21 19:25:45 vamad kernel: [ 45.310448] radeon 0000:00:01.0: Wait for MC idle timedout !
Oct 21 19:25:45 vamad kernel: [ 45.462622] radeon 0000:00:01.0: Wait for MC idle timedout !
Oct 21 19:25:45 vamad kernel: [ 45.464578] [drm] PCIE GART of 512M enabled (table at 0x0000000000040000).
Oct 21 19:25:45 vamad kernel: [ 45.464662] radeon 0000:00:01.0: WB enabled
Oct 21 19:25:45 vamad kernel: [ 45.464665] [drm] fence driver on ring 0 use gpu addr 0x20000c00 and cpu addr 0xffff880211579c00
Oct 21 19:25:46 vamad kernel: [ 45.630581] [drm:r600_ring_test] *ERROR* radeon: ring 0 test failed (scratch(0x8500)=0xCAFEDEAD)
Oct 21 19:25:46 vamad kernel: [ 45.630583] [drm:evergreen_resume] *ERROR* evergreen startup failed on resume

a také je tam plno zpráv tohoto typu:

Oct 21 19:25:48 vamad dbus-daemon[627]: (process:4146): GLib-WARNING **: goption.c:2179: ignoring no-arg, optional-arg or filename flags (16) on option of arg-type 1 in entry (null):helper-dir
Oct 21 19:25:48 vamad dbus-daemon[627]: dbus[627]: [system] Successfully activated service 'org.freedesktop.UDisks'
Oct 21 19:25:48 vamad dbus[627]: [system] Successfully activated service 'org.freedesktop.UDisks'
Oct 21 19:25:48 vamad dbus-daemon[627]: **** pci ADDING /sys/devices/pci0000:00/0000:00:00.0
Oct 21 19:25:48 vamad dbus-daemon[627]: **** pci IGNORING ADD /sys/devices/pci0000:00/0000:00:00.0
Oct 21 19:25:48 vamad dbus-daemon[627]: **** pci ADDING /sys/devices/pci0000:00/0000:00:01.0
Oct 21 19:25:48 vamad dbus-daemon[627]: **** pci IGNORING ADD /sys/devices/pci0000:00/0000:00:01.0
Oct 21 19:25:48 vamad dbus-daemon[627]: **** pci ADDING /sys/devices/pci0000:00/0000:00:01.1
Oct 21 19:25:48 vamad dbus-daemon[627]: **** pci IGNORING ADD /sys/devices/pci0000:00/0000:00:01.1
Oct 21 19:25:48 vamad dbus-daemon[627]: **** pci ADDING /sys/devices/pci0000:00/0000:00:02.0
Oct 21 19:25:48 vamad dbus-daemon[627]: **** pci IGNORING ADD /sys/devices/pci0000:00/0000:00:02.0
Oct 21 19:25:48 vamad dbus-daemon[627]: **** pci ADDING /sys/devices/pci0000:00/0000:00:04.0
Oct 21 19:25:48 vamad dbus-daemon[627]: **** pci IGNORING ADD /sys/devices/pci0000:00/0000:00:04.0
...

Nenapadá někoho, v čem by mohl být problém (ta hromada zpráv se mi nelíbí) - odchází grafika?

Děkuji a zdravím