diff --git a/documentation/ref-manual/ref-variables.xml b/documentation/ref-manual/ref-variables.xml
index 2ebf88a4fd..995d9f2d14 100644
--- a/documentation/ref-manual/ref-variables.xml
+++ b/documentation/ref-manual/ref-variables.xml
@@ -2159,7 +2159,10 @@
                 <para>
                     Configures the GNU GRand Unified Bootloader (GRUB) to have
                     graphics and serial in the boot menu.
-                    Set this variable to "1" to enable both in the menu.
+                    Set this variable to "1" in your
+                    <filename>local.conf</filename> or distribution
+                    configuration file to enable graphics and serial
+                    in the menu.
                 </para>
 
                 <para>