Mám stejný problém (nesouvisí ale s Dashem), prostě po nějaké době, zřejmě když je systém víc zatížen třeba mnoha otevřenými záložkami ve Firefoxu a programy, se obraz takto rozsype.
údaje o grafice:
hwinfo --gfxcard
> hal.1: read hal dataprocess 1941: arguments to dbus_move_error() were incorrect, assertion "(dest) == NULL || !dbus_error_is_set ((dest))" failed in file ../../dbus/dbus-errors.c line 282.
This is normally a bug in some application using the D-Bus library.
libhal.c 3483 : Error unsubscribing to signals, error=The name org.freedesktop.Hal was not provided by any .service files
10: PCI 02.0: 0300 VGA compatible controller (VGA)
[Created at pci.318]
Unique ID: _Znp.6hbt4sH03yA
SysFS ID: /devices/pci0000:00/0000:00:02.0
SysFS BusID: 0000:00:02.0
Hardware Class: graphics card
Model: "Intel 915 G"
Vendor: pci 0x8086 "Intel Corporation"
Device: pci 0x2582 "915 G"
SubVendor: pci 0x103c "Hewlett-Packard Company"
SubDevice: pci 0x300a
Revision: 0x04
Driver: "i915"
Driver Modules: "drm"
Memory Range: 0xcfd00000-0xcfd7ffff (rw,non-prefetchable)
I/O Ports: 0x1800-0x1807 (rw)
Memory Range: 0xe0000000-0xefffffff (ro,non-prefetchable)
Memory Range: 0xcfd80000-0xcfdbffff (rw,non-prefetchable)
IRQ: 16 (21612 events)
Module Alias: "pci:v00008086d00002582sv0000103Csd0000300Abc03sc00i00"
Driver Info #0:
XFree86 v4 Server Module: intel
Driver Info #1:
XFree86 v4 Server Module: intel
3D Support: yes
Extensions: dri
Config Status: cfg=new, avail=yes, need=no, active=unknown
Primary display adapter: #10