diff --git a/qemu/tests/cfg/balloon_service.cfg b/qemu/tests/cfg/balloon_service.cfg
index ddbbd44e9360a8084537129099ced5411d754c33..d4f91bff6f75fcb43276bd33cfc4d07018401a92 100644
--- a/qemu/tests/cfg/balloon_service.cfg
+++ b/qemu/tests/cfg/balloon_service.cfg
@@ -10,6 +10,7 @@
     balloon_dev_add_bus = yes
     Windows:
         driver_name = "balloon"
+        guest_compare_threshold = 300
         cdroms = "cd1 winutils virtio"
         # Please change following cdrom_virtio to the right version
         # if necessary