wait for vertical blank

whats this supposed to be? vsync? also i noticed it came disabled in 0.86 and now its enabled by default... whats the best setting for this?
thanks in advance

[J7N]

This is a good question. Is this forced vsync supposed to improve quality? Always? What is your experience with "waith for vertical blank" on?

I am noticing that my comp is not able to display clips with smooth scrolling picture and looking forward to fix the problem. Would setting the refresh rate to exact multiple of frame rate help?