FYI: triple monitors, two graphics cards, one sync error, oh my

Hi,

I'm just posting this in case someone else has the some problem I did.

Under Windows, with a three monitor (multi-monitor) setup using a
dual-head graphics card in spanning mode and single-head graphics
card, the spanned monitor has to be the primary display monitor or PTB
throws a sync error.

The simplest solution is to make the spanned monitor the primary
monitor and use the graphics's card's software to force all windows to
open on the operators display (single-head). This is easy for nVidia.

From what I gathered looking at old messages, PTB queries the primary
display for the beam position, regardless of which screen you're
trying to open, and when syncing this obviously fails if it queries
the beam position of one graphics card and then uses that info for
syncing on a different graphics card.

I hope that helps someone :-)

Best,

-Sam