diff --git a/build/pdp10-ka/start b/build/pdp10-ka/start
index d40db3a9..b13c7399 100755
--- a/build/pdp10-ka/start
+++ b/build/pdp10-ka/start
@@ -44,7 +44,7 @@ tvcon() {
 }
 
 xgp11() {
-    (sleep 3; tools/tv11/xgp11 -s1 -f ten11.1 >xgp11.log 2>&1) &
+    (sleep 3; tools/tv11/xgp11 -s4 -f ten11.1 >xgp11.log 2>&1) &
     started XGP-11 "$!"
 }