I found a post on this forum stating
With SuperLab 4.0, stimulus presentations are synchronized with the refresh rate of the screen on Windows XP and 2000, and on Mac OS 10.4, but not on Mac OS 10.3.9.
Is this also true of the version of SuperLab I’m using (on Windows XP)? How precise can the presentation times be (e.g. of a stimulus followed by a mask)?