https://bugs.freedesktop.org/show_bug.cgi?id=28771
--- Comment #8 from Sven Arvidsson sa@whiz.se 2010-07-16 06:30:13 PDT --- I can confirm that setting vblank_mode=0 in drirc doesn't work here either.
Can't reproduce the other problem though, window or fullscreen doesn't make a difference.