I am running a graphics toolbox using Matlab called Psychophysics. I am this close to getting everything working, but I'm having drama with synchronization errors which has to do with my driver settings. Check this post out:
He says the error below is most likely due to a few options needed to be reset, most notably
Option "TripleBuffer" "off" Option "SwapbuffersWait" "on"
My question is how do I even reset these values? He mentioned the xorg.conf file, but I've read in many different places that this file isn't used anymore. I can't find it using the 'find /usr -name xorg.conf' unix command on my system either (and that would take forever). I'm also afraid I will ruin my graphics card if I don't talk to someone who knows their stuff.
Here is my error message:
PTB-INFO: No low-level controllable GPU on screenId 0. Beamposition timestamping and other special functions disabled. PTB-DEBUG:PsychOSGetSwapCompletionTimestamp: This likely means a driver bug or malfunction, or that timestamping support has been disabled by the user in the driver! PTB-INFO: OpenGL-Renderer is Intel Open Source Technology Center :: Mesa DRI Intel(R) Sandybridge Mobile :: 3.0 Mesa 10.1.3 PTB-INFO: VBL startline = 768 , VBL Endline = -1 PTB-INFO: Will try to use OS-Builtin OpenML sync control support for accurate Flip timestamping. PTB-INFO: Measured monitor refresh interval from VBLsync = 16.682734 ms [59.942213 Hz]. (297 valid samples taken, stddev=0.322476 ms.) PTB-INFO: Reported monitor refresh interval from operating system = 16.646968 ms [60.070999 Hz]. PTB-INFO: Small deviations between reported values are normal and no reason to worry. WARNING: Couldn't compute a reliable estimate of monitor refresh interval! Trouble with VBL syncing?!? ----- ! 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.