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
@@ -379,7 +379,7 @@ static LRESULT CALLBACK WndProcGdi(HWND 
 
 			SelectPalette(hDC, hOldPalette, TRUE);
 			ReleaseDC(hwnd, hDC);
-			if (nChanged) InvalidateRect(hwnd, NULL, FALSE);
+			if (nChanged != 0) InvalidateRect(hwnd, NULL, FALSE);
 			return 0;
 		}