Error using Screen function due to use of deficient Intel graphics on MS-Windows

Dear members of this forum, I am finalising my experiment using PSB in Matlab version R2023a, but encounter a rather strange error that often returns regarding the command

if nargin < 2 || isempty(windowrect) windowrect = []; end screenid = max(Screen('Screens')); win = Screen('OpenWindow', screenid, 0, windowrect);

My script opens a video and plays it multiple times after each other. This works 90% of the times but 10% of the times my script fails to start and I get the following error:

PTB-INFO: This is Psychtoolbox-3 for Microsoft Windows, under Matlab 64-Bit (Version 3.0.19 - Build date: Feb 20 2023).
PTB-INFO: OS support status: Windows 11 (Version 11.0) is not supported.
PTB-INFO: Type ‘PsychtoolboxVersion’ for more detailed version information.
PTB-INFO: Most parts of the Psychtoolbox distribution are licensed to you under terms of the MIT License, with
PTB-INFO: some restrictions. See file ‘License.txt’ in the Psychtoolbox root folder for the exact licensing conditions.

PTB-INFO: For information about paid support, support memberships and other commercial services, please type
PTB-INFO: ‘PsychPaidSupportAndServices’.

PTB-INFO: The detected endline of the vertical blank interval is equal or lower than the startline. This indicates
PTB-INFO: that i couldn’t detect the duration of the vertical blank interval and won’t be able to correct timestamps
PTB-INFO: for it. This will introduce a very small and constant offset (typically << 1 msec). Read ‘help BeampositionQueries’
PTB-INFO: for how to correct this, should you really require that last few microseconds of precision.
PTB-INFO: Btw. this can also mean that your systems beamposition queries are slightly broken. It may help timing precision to
PTB-INFO: enable the beamposition workaround, as explained in ‘help ConserveVRAMSettings’, section ‘kPsychUseBeampositionQueryWorkaround’.

PTB-INFO: OpenGL-Renderer is Intel :: Intel(R) UHD Graphics 750 :: 4.6.0 - Build
PTB-INFO: VBL startline = 1080 , VBL Endline = 1079
PTB-INFO: Measured monitor refresh interval from beamposition = 16.666690 ms [59.999917 Hz].
PTB-INFO: Will use beamposition query for accurate Flip time stamping.
PTB-INFO: Measured monitor refresh interval from VBLsync = 16.666764 ms [59.999650 Hz]. (50 valid samples taken, stddev=0.267313 ms.)
PTB-INFO: Reported monitor refresh interval from operating system = 16.666667 ms [60.000000 Hz].
PTB-INFO: Small deviations between reported values are normal and no reason to worry.
PTB-INFO: ==============================================================================================================================
PTB-INFO: WINDOWS DWM DESKTOP COMPOSITOR IS ACTIVE. On this Windows-10 or later system, Psychtoolbox can no longer reliably detect if
PTB-INFO: this will cause trouble for timing and integrity of visual stimuli or not. You might be just fine, or you could be in trouble.
PTB-INFO: Use external measurement equipment and independent procedures to verify reliability of timing if you care about proper timing.
PTB-INFO: ==============================================================================================================================

WARNING: Couldn’t compute a reliable estimate of monitor refresh interval! Trouble with VBL syncing?!?


One or more internal checks (see Warnings above) indicate that synchronization
of Psychtoolbox to the vertical retrace (VBL) is not working on your setup.

This will seriously impair proper stimulus presentation and stimulus presentation timing!
Please read ‘help SyncTrouble’ for information about how to solve or work-around the problem.
You can force Psychtoolbox to continue, despite the severe problems, by adding the command
Screen(‘Preference’, ‘SkipSyncTests’, 1); at the top of your script, if you really know what you are doing.

Error using Screen
See error message printed above.

Error in visualonly (line 70)
win = Screen(‘OpenWindow’, screenid, 0, windowrect);

Most of the time it does not display such error. Without changing any lines, it crashes every once in a while. Could someone help me and explain the cause of this issue?

I am working on a 64-bit operating PC using Windows 11.

Thank you for any tips or explanations.
Have a nice day,

There can be multiple reasons for this. Read the help text recommended in the error message. Also search this forum for multiple posts on the same topic.


1 Like