Extreme slow screen refresh Blender 2nd display

Win10

2 NVIDIA GTX 970

2 Displays each on one GPU

Blender runs perfect on the first display.

When I move it onto the second display it turns into incredible stop motion.

Happens mainly in full screen

Any idea what this could be?

Doesn’t happen under OS X for me.

Do you have the second display plugged into the same GPU as the first display? if not that’s probably why it doesn’t work well.

Each Dell Display is at one GPU.

Happens mainly in full screen