Hi Keith,
Thank you for taking the time to respond.
I am not sure about the video card specification between my old and new setup, but both use Windows as the OS.
Here are the outputs of the VBLSyncTest ran on my new set up (after turning off sync attempts, as you suggested):
- For refresh rate fixed at 60 Hz
PTB-INFO: This is Psychtoolbox-3 for Microsoft Windows, under Matlab 64-Bit (Version 3.0.19 - Build date: Jul 31 2024).
PTB-INFO: OS support status: Windows 10 (Version 10.0) supported and tested to some limited degree.
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: OpenGL-Renderer is ATI Technologies Inc. :: AMD Radeon(TM) Graphics :: 4.6.0 Compatibility Profile Context 24.9.1.240813
PTB-INFO: VBL startline = 1080 , VBL Endline = 1120
PTB-INFO: Measured monitor refresh interval from beamposition = 16.666622 ms [60.000159 Hz].
PTB-INFO: Will use beamposition query for accurate Flip time stamping.
PTB-INFO: Measured monitor refresh interval from VBLsync = 16.669242 ms [59.990730 Hz]. (50 valid samples taken, stddev=0.110155 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: ==============================================================================================================================
The refresh interval reported by the operating system is 16.66667 ms.
Measured refresh interval, as reported by "GetFlipInterval" is 16.66924 ms. (nsamples = 0, stddev = 0.00000 ms)
INFO: PTB's Screen('Flip', 10) command seems to have missed the requested stimulus presentation deadline
INFO: a total of 2 times out of a total of 607 flips during this session.
INFO: This number is fairly accurate (and indicative of real timing problems in your own code or your system)
INFO: if you provided requested stimulus onset times with the 'when' argument of Screen('Flip', window [, when]);
INFO: If you called Screen('Flip', window); without the 'when' argument, this count is more of a ''mild'' indicator
INFO: of timing behaviour than a hard reliable measurement. Large numbers may indicate problems and should at least
INFO: deserve your closer attention. Cfe. 'help SyncTrouble', the FAQ section at www.psychtoolbox.org and the
INFO: examples in the PDF presentation in PsychDocumentation/Psychtoolbox3-Slides.pdf for more info and timing tips.
WARNING: This session of your experiment was run by you with the setting Screen('Preference', 'SkipSyncTests', 1).
WARNING: This means that some internal self-tests and calibrations were skipped. Your stimulus presentation timing
WARNING: may have been wrong. This is fine for development and debugging of your experiment, but for running the real
WARNING: study, please make sure to set Screen('Preference', 'SkipSyncTests', 0) for maximum accuracy and reliability.
PTB missed 1 out of 600 stimulus presentation deadlines.
One missed deadline is ok and an artifact of the measurement.
PTB completed 0 stimulus presentations before the requested target time.
Have a look at the plots for more details...
- For refresh rate fixed at 120 Hz
PTB-INFO: This is Psychtoolbox-3 for Microsoft Windows, under Matlab 64-Bit (Version 3.0.19 - Build date: Jul 31 2024).
PTB-INFO: OS support status: Windows 10 (Version 10.0) supported and tested to some limited degree.
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-WARNING: Couldn't even collect one single valid flip interval sample! Sanity range checks failed!
PTB-WARNING: Could be a system bug, or a temporary timing problem. Retrying the procedure might help if
PTB-WARNING: the latter is the culprit.
WARNING: VBL Calibration run No. 1 failed. Retrying...
PTB-WARNING: Couldn't even collect one single valid flip interval sample! Sanity range checks failed!
PTB-WARNING: Could be a system bug, or a temporary timing problem. Retrying the procedure might help if
PTB-WARNING: the latter is the culprit.
WARNING: VBL Calibration run No. 2 failed. Retrying...
WARNING: Will enable VBL busywait-workaround before trying final VBL Calibration run No. 3.
WARNING: This will hopefully work-around graphics driver bugs of the GPU sync-to-retrace mechanism. Cross your fingers!
PTB-WARNING: Couldn't even collect one single valid flip interval sample! Sanity range checks failed!
PTB-WARNING: Could be a system bug, or a temporary timing problem. Retrying the procedure might help if
PTB-WARNING: the latter is the culprit.
PTB-INFO: OpenGL-Renderer is ATI Technologies Inc. :: AMD Radeon(TM) Graphics :: 4.6.0 Compatibility Profile Context 24.9.1.240813
PTB-INFO: VBL startline = 1080 , VBL Endline = 1120
PTB-INFO: Measured monitor refresh interval from beamposition = 16.666669 ms [59.999990 Hz].
PTB-INFO: Will use beamposition query for accurate Flip time stamping.
PTB-INFO: Measured monitor refresh interval from VBLsync = 0.000000 ms [inf Hz]. (0 valid samples taken, stddev=10000000.000000 ms.)
PTB-INFO: Reported monitor refresh interval from operating system = 8.333333 ms [120.000000 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?!?
WARNING: Mismatch between measured monitor refresh interval and interval reported by operating system.
This indicates massive problems with VBL sync.
PTB-WARNING: Unable to measure monitor refresh interval! Using a fake value of 8.333333 milliseconds.
----- ! PTB - ERROR: SYNCHRONIZATION FAILURE ! -----
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.
PTB-WARNING: Mismatch between measured monitor refresh intervals! This indicates problems with rasterbeam position queries.
----- ! PTB - WARNING: SYNCHRONIZATION TROUBLE ! -----
One or more internal checks (see Warnings above) indicate that
queries of rasterbeam position are not properly working for your setup.
Psychtoolbox will work around this by using a different timing algorithm,
but it will cause Screen('Flip') to report less accurate/robust timestamps
for stimulus timing.
Read 'help BeampositionQueries' for more info and troubleshooting tips.
The refresh interval reported by the operating system is 8.33333 ms.
Measured refresh interval, as reported by "GetFlipInterval" is 8.33333 ms. (nsamples = 0, stddev = 0.00000 ms)
INFO: PTB's Screen('Flip', 10) command seems to have missed the requested stimulus presentation deadline
INFO: a total of 606 times out of a total of 607 flips during this session.
INFO: This number is fairly accurate (and indicative of real timing problems in your own code or your system)
INFO: if you provided requested stimulus onset times with the 'when' argument of Screen('Flip', window [, when]);
INFO: If you called Screen('Flip', window); without the 'when' argument, this count is more of a ''mild'' indicator
INFO: of timing behaviour than a hard reliable measurement. Large numbers may indicate problems and should at least
INFO: deserve your closer attention. Cfe. 'help SyncTrouble', the FAQ section at www.psychtoolbox.org and the
INFO: examples in the PDF presentation in PsychDocumentation/Psychtoolbox3-Slides.pdf for more info and timing tips.
WARNING: This session of your experiment was run by you with the setting Screen('Preference', 'SkipSyncTests', 1).
WARNING: This means that some internal self-tests and calibrations were skipped. Your stimulus presentation timing
WARNING: may have been wrong. This is fine for development and debugging of your experiment, but for running the real
WARNING: study, please make sure to set Screen('Preference', 'SkipSyncTests', 0) for maximum accuracy and reliability.
PTB missed 599 out of 600 stimulus presentation deadlines.
One missed deadline is ok and an artifact of the measurement.
PTB completed 0 stimulus presentations before the requested target time.
Have a look at the plots for more details...
I have posted an update on my original post as well: seems the monitor itself as an issue, because keeping all else constant (HDMI connection, PC, OS, refresh rate), the script works on my previous monitor but not on my current one. I will try to shift to Linux for more accurate control on timing.