diff --git a/SourceGen/RuntimeData/Commodore/VisC64.cs b/SourceGen/RuntimeData/Commodore/VisC64.cs
index 082a316..e015107 100644
--- a/SourceGen/RuntimeData/Commodore/VisC64.cs
+++ b/SourceGen/RuntimeData/Commodore/VisC64.cs
@@ -434,7 +434,7 @@ namespace RuntimeData.Commodore {
 
         private const byte TRANSPARENT = 16;
 #if SHOW_BORDER
-        private const byte BORDER_COLOR = 0;
+        private const byte BORDER_COLOR = 17;
 #else
         private const byte BORDER_COLOR = TRANSPARENT;
 #endif
@@ -459,6 +459,9 @@ namespace RuntimeData.Commodore {
             vb.SetColor(14, 0xff, 0x6c, 0x5e, 0xb5);    // 14=light blue
             vb.SetColor(15, 0xff, 0x95, 0x95, 0x95);    // 15=light grey
             vb.SetColor(16, 0, 0, 0, 0);                // 16=transparent
+#if SHOW_BORDER
+            vb.SetColor(17, 0xff, 0x00, 0xd6, 0xff);    // 17=grid border
+#endif
         }
     }
 }