https://bugs.winehq.org/show_bug.cgi?id=39421
--- Comment #3 from Jonas Maebe jonas.bugzilla@gmail.com ---
I'm also not sure whether it would help, but looking at the ddraw log (which I will also attach -- it's a trace+ddraw,trace+d3d_draw log), I think it may since often there are several blits between the vsync waits.
Well, at least if Wine is allowed to and would queue flushes until a request to wait for the vsync is fired...