Re: problème synchro VBL

1
Hi Fabien,

in case you use windows (7), did you try "net stop uxsms" on the
command line before using screen? It will switch off the desktop
compositor and increase the likelihood of a working vsync. You have to
have administrator rights to do so!

Nvidia (GeForce GTX 260) works for me on a desktop PC. Intel HD 4600
integrated graphics did work as well on a notebook, but not on a
desktop PC. I think it is dependent on the drivers, if a graphics card
achieves synchronization.

Bonne chance,
Christian
2
PTB automatically disables the desktop compositor on Windows Vista and 7, so that command wouldn't be strictly neccessary, although it would avoid the flickering every time the disable and reenable happens at the start and end of a PTB session. The story is different on Windows-8 where we can't disable the compositor or even check if it is disabled, as Microsoft decided to remove that functionality from the OS. On Windows-8 and later it's simply "hope for the best and expect the worst".

I guess more information would be needed to find out what's wrong, or if it is just a system with bad timing behaviour. Also preferrably in english.

-mario