# Using Two screens with psychtoolbox

**URL:** <https://psychtoolbox.discourse.group/t/using-two-screens-with-psychtoolbox/269>\
**Category:** Uncategorized\
**Created:** [July 8, 2014, 5:54pm UTC](https://psychtoolbox.discourse.group/t/using-two-screens-with-psychtoolbox/269 "2014-07-08T17:54:49Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![smarulan](https://avatars.discourse-cdn.com/v4/letter/s/4af34b/32.png) [@smarulan](https://psychtoolbox.discourse.group/u/smarulan)\
**Post date:** [July 8, 2014, 5:54pm UTC](https://psychtoolbox.discourse.group/t/using-two-screens-with-psychtoolbox/269/1 "2014-07-08T17:54:49Z")

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I am trying to run an experiment using a mac OSX 10.9.4 with an intel HD graphics 4000. I am running my experiment using a second display in non-mirror mode. I downloaded the most recent update of the psych toolbox but I continue to get this problem:

PTB-INFO: Connection to Psychtoolbox kernel support driver instance #0 (Revision 0) established.

PTB-INFO: Disconnecting from kernel driver instance #0 for detected Intel GPU for safety reasons. setenv('PSYCH\_ALLOW\_DANGEROUS', '1') to override.

PTB-INFO: Running on OSX 10.9+ - Enabling protection against AppNap and other evils.

PTB-INFO: This is Psychtoolbox-3 for Apple OS X, under Matlab 64-Bit (Version 3.0.11 - Build date: Apr &nbsp;6 2014).

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: Using Cocoa for this fullscreen window to work around various graphics driver bugs in OSX 10.8 and later.

PTB-INFO: Presentation timing accuracy may suffer and timestamps may be unreliable, depending on your specific setup.

PTB-INFO: Deficient Apple OS/X 10.7 or later detected: Would use fragile CoreVideo timestamping as fallback,

PTB-INFO: if beamposition timestamping would not work. Will try to use beamposition timestamping if possible.

PTB-INFO: Installation of the PsychtoolboxKernelDriver is strongly recommended if you care about precise visual

PTB-INFO: onset timestamping or timing. See 'help PsychtoolboxKernelDriver' for installation instructions.

PTB-INFO: However, if you use a Intel graphics card then don't bother, as the driver is no longer useful on such a card.

PTB-INFO: You are using a multi-display setup (2 active displays):

PTB-INFO: Please read 'help MultiDisplaySetups' for specific information on the Do's, Dont's,

PTB-INFO: and possible causes of trouble and how to diagnose and resolve them.

PTB-INFO: According to the operating system, some of your connected displays do not seem to&nbsp;

PTB-INFO: be switched into mirror mode. For a discussion of mirror mode vs. non-mirror mode,

PTB-INFO: please read 'help MirrorMode'.

PTB-INFO: OpenGL-Renderer is Intel Inc. :: Intel HD Graphics 4000 OpenGL Engine :: 2.1 INTEL-8.28.30

PTB-INFO: Renderer has 1024 MB of VRAM and a maximum 1024 MB of texture memory.

PTB-INFO: VBL startline = 1200 , VBL Endline = -1

PTB-INFO: Beamposition queries unsupported on this system. Will try to use kernel-level vbl interrupts as fallback.

PTB-INFO: Measured monitor refresh interval from VBLsync = 16.721588 ms [59.802933 Hz]. (50 valid samples taken, stddev=0.080377 ms.)

PTB-INFO: Small deviations between reported values are normal and no reason to worry.

PTB-INFO: Support for fast OffscreenWindows enabled.

Any help would be greatly appreciated&nbsp;

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