Control Frame Rate for PsychoPy Window

Coding
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1

Hi All,

I’m trying to run an experiment where I want to display a stimulus at a given frequency (60Hz). I’ve programmed the display to set Vsync at a fixed interval. After creating the window and ImageStim instances, I call the draw and flip commands to display the stimuli.

I notice that the window.flip event takes only 5.5ms to complete (i.e it runs at 180FPS). This contradicts the 60FPS setting on the display which should ensure that the window.flip event should be spaced out by 16.6ms. I’ve set waitBlanking=True while creating the Window Object.

I also notice there are quite a few frames being dropped (using the nDroppedFrames attribute of the display).

Any leads on what I may be doing wrong here?

Thank you,
Shravan

2

Is it an Nvidia GPU with Gsync? If so, can you disable that?

3

Yes, it is a Nvidia GPU, however, I’m running the nouveau display driver and I doubt GSync is enabled by default. Is there any way I can determine the number of frames actually posted onto the display?