Registro de mensajes de error al arrancar el sistema

Hola a todos, al cargar el sistema después de actualizar a 4.0 se producen una serie de mensajes (no hay splash) una parte de ellos relativos a errores de la tarjeta gráfica. El sistema termina cargando correctamente pero me preocupa que algún problema con el controlador pueda causar daños a la tarjeta. Pongo los primeros que he encontrado en el fichero dmsg (son muchos pero aparentemente repetitivos) por si alguien puede indicarme de qué se trata y si es importante y/o tiene solución:

_gem_object_create] *ERROR* Failed to allocate GEM object (7258112, 2, 4096, -22)
[ 25.654204] [drm:radeon_gart_bind] *ERROR* trying to bind memory to unitialized GART !
[ 25.654207] [drm:radeon_ttm_backend_bind] *ERROR* failed to bind 1000 pages at 0x00000000
[ 25.654209] [TTM] Couldn't bind backend.
[ 25.654383] radeon 0000:01:00.0: object_init failed for (4096000, 0x00000002)
[ 25.654386] [drm:radeon_gem_object_create] *ERROR* Failed to allocate GEM object (4096000, 2, 4096, -22)
[ 25.659128] [drm:radeon_gart_bind] *ERROR* trying to bind memory to unitialized GART !
[ 25.659131] [drm:radeon_ttm_backend_bind] *ERROR* failed to bind 1772 pages at 0x00000000
[ 25.659132] [TTM] Couldn't bind backend.
[ 25.659447] radeon 0000:01:00.0: object_init failed for (7258112, 0x00000002)
[ 25.659450] [drm:radeon_gem_object_create] *ERROR* Failed to allocate GEM object (7258112, 2, 4096, -22)
[ 25.665247] [drm:radeon_gart_bind] *ERROR* trying to bind memory to unitialized GART !
[ 25.665250] [drm:radeon_ttm_backend_bind] *ERROR* failed to bind 1000 pages at 0x00000000
[ 25.665252] [TTM] Couldn't bind backend.
[ 25.665427] radeon 0000:01:00.0: object_init failed for (4096000, 0x00000002)
[ 25.665429] [drm:radeon_gem_object_create] *ERROR* Failed to allocate GEM object (4096000, 2, 4096, -22)
[ 25.670171] [drm:radeon_gart_bind] *ERROR* trying to bind memory to unitialized GART !
[ 25.670173] [drm:radeon_ttm_backend_bind] *ERROR* failed to bind 1772 pages at 0x00000000
[ 25.670175] [TTM] Couldn't bind backend.

Un saludo y gracias.