diff --git a/src/video/win32_v.cpp b/src/video/win32_v.cpp
--- a/src/video/win32_v.cpp
+++ b/src/video/win32_v.cpp
@@ -197,7 +197,7 @@
 		/* redraw screen */
 		if (_wnd.running) {
 			_screen.dst_ptr = _wnd.buffer_bits;
-			UpdateWindows();
+			MarkWholeScreenDirty();
 		}
 
 		if (_draw_mutex != NULL) _draw_mutex->EndCritical();