diff --git a/src/video/allegro_v.cpp b/src/video/allegro_v.cpp
--- a/src/video/allegro_v.cpp
+++ b/src/video/allegro_v.cpp
@@ -417,6 +417,8 @@ const char *VideoDriver_Allegro::Start(c
 	}
 	_allegro_instance_count++;
 
+	this->UpdateAutoResolution();
+
 	install_timer();
 	install_mouse();
 	install_keyboard();