diff --git a/tests/conform/test-conform-common.c b/tests/conform/test-conform-common.c
index d64c72f74..8ff8d0d6f 100644
--- a/tests/conform/test-conform-common.c
+++ b/tests/conform/test-conform-common.c
@@ -1,5 +1,10 @@
 #include <clutter/clutter.h>
 
+#ifdef COGL_HAS_XLIB
+#include <X11/Xlib.h>
+#include <clutter/x11/clutter-x11.h>
+#endif
+
 #include "test-conform-common.h"
 
 /**
@@ -21,6 +26,18 @@ test_conform_simple_fixture_setup (TestConformSimpleFixture *fixture,
                 "If you want to run all the tests you should run\n"
                 "$ make test-report");
   counter++;
+
+#ifdef COGL_HAS_XLIB
+  /* A lot of the tests depend on a specific stage / framebuffer size
+   * when they read pixels back to verify the results of the test.
+   *
+   * Normally the asynchronous nature of X means that setting the
+   * clutter stage size may really happen an indefinite amount of time
+   * later but since the tests are so short lived and may only render
+   * a single frame this is not an acceptable semantic.
+   */
+  XSynchronize (clutter_x11_get_default_display(), TRUE);
+#endif
 }