diff --git a/intern/cycles/blender/blender_object.cpp b/intern/cycles/blender/blender_object.cpp
index 67255d9f707..e8fa5c0ff3d 100644
--- a/intern/cycles/blender/blender_object.cpp
+++ b/intern/cycles/blender/blender_object.cpp
@@ -267,10 +267,15 @@ Object *BlenderSync::sync_object(BL::Object b_parent, int persistent_id[OBJECT_P
 		object->motion.post = tfm;
 		object->use_motion = false;
 
+		/* random number */
 		object->random_id = hash_string(object->name.c_str());
-		if(persistent_id)
+
+		if(persistent_id) {
 			for(int i = 0; i < OBJECT_PERSISTENT_ID_SIZE; i++)
 				object->random_id = hash_int_2d(object->random_id, persistent_id[i]);
+		}
+		else
+			object->random_id = hash_int_2d(object->random_id, 0);
 
 		/* visibility flags for both parent */
 		object->visibility = object_ray_visibility(b_ob) & PATH_RAY_ALL;
diff --git a/release/scripts/startup/bl_ui/space_userpref.py b/release/scripts/startup/bl_ui/space_userpref.py
index 3c426ade54b..de55eaba775 100644
--- a/release/scripts/startup/bl_ui/space_userpref.py
+++ b/release/scripts/startup/bl_ui/space_userpref.py
@@ -422,7 +422,7 @@ class USERPREF_PT_system(Panel):
         col.separator()
         col.separator()
 
-        if hasattr(system, "compute_device"):
+        if hasattr(system, "compute_device_type"):
             col.label(text="Compute Device:")
             col.row().prop(system, "compute_device_type", expand=True)
             sub = col.row()