When running in full screen, the execution screen is displayed between the two monitors

I am running PTB on a laptop in this environment.

Ubuntu 20.04.6 LTS
Matlab 2023a for linux
Intel(R) Core™ i7-10750H CPU @ 2.60GHz
NVIDIA GeForce GTX 1650 Ti

I work on dual display, a laptop and an external display. When run in full screen, the screen appeared in between the two displays. Then, I tried to get the number of displays recognized by “Screen(‘Screens’)” and found that only one display was recognized.
The system recognizes both displays.
I searched for the same question but could not find it. What steps can I take to resolve this?

Thank you.

Make sure both screens are connected before starting matlab. So please close and restart matlab while leaving the second screen connected and see if that solves your problem

That’s normal on Linux. If you only want one display for visual stimulation, and one for the operator with the desktop GUI, you would need to use XOrgConfCreator and XOrgConfSelector to create and install a suitable config file for dual-X-Screen operation.

However, this is a hybrid graphics / dual-gpu laptop, which would be utterly useless on MS-Windows if visual timing precision is of any concern, and generally recommended to avoid in some cases on Linux (although not hopeless), due to increased setup complexity and some limitations. XOrgConfCreator can not automatically handle all of these laptops, depending on the very specifics on how this laptop model is designed. What specific model of laptop is this (link to manufacturer product description)? See help HybridGraphics for specific setup steps and remarks for different combinations of graphics cards, laptop types and operating systems. The “NVidia Optimus” section is the right one.

Intel + NVidia proprietary graphics driver has not been validated in years, due to lack of suitable hardware. It is expected, but not guaranteed, to be reasonably workable with proper configuration though.

If you run into trouble, help PsychPaidSupportAndServices will tell you how to create an authentication token for the paid support membership for up to 30 minutes of further advice. Unless your lab already has a valid and active membership, as it should have but many labs foolishly don’t have, it may happen that a fresh bought license won’t get activated before I go on extended christmas/new years vacation though, as key activation can take 5-10 working days from the date of receipt of payment. In that case I’d be on vacation, and paid advice would have to wait until at least mid- to late January 2024.

Good luck,