diff --git distrib/amd64/common/install.md distrib/amd64/common/install.md
index d4fc8418a97..0c9db939463 100644
--- distrib/amd64/common/install.md
+++ distrib/amd64/common/install.md
@@ -35,7 +35,7 @@ MDXAPERTURE=2
 MDXDM=y
 NCPU=$(sysctl -n hw.ncpufound)
 
-if dmesg | grep -q 'efifb0 at mainbus0'; then
+if dmesg | egrep -q 'efifb0? at mainbus0'; then
 	MDEFI=y
 fi