Created attachment 1311152 [details]
The Xorg log file when the issue happens (out of the box fedora 26)

Description of problem:
I have one monitor driven by an AMD GPU and two monitors driven by a NVIDIA GPU. On the two NVIDIA-driven monitors the screen fails to refresh properly. This is most notable when inputting text. For example, when typing into an xterm the first character may appear but no more appear until the return key is pressed (and then the screen is refreshed properly).

Version-Release number of selected component (if applicable):
xorg-x11-server-Xorg-1.19.3-4.fc26.x86_64

How reproducible:
Always (with this hardware configuration). It can be reproduced using the fedora 26 mate live image.

Steps to Reproduce:
1. Log in and then, if necessary (eg using mate live image), enable the additional monitors (using the GUI for altering the display ie mate-display-properties).
2. Start a mate terminal and move it to one of the nvidia-driven monitors.
3. Enter some text into the mate terminal.

Actual results:
Text fails to appear properly in the xterm window, until the return key is pressed.

Expected results:
Text should appear as soon as it is typed.

Additional info:
AMD GPU: Radeon HD 4250 (RS880)
NVIDIA GPU: Quadro NVS 295 (G98)
No /etc/X11/xorg.conf

This hardware configuration was working okay in fedora 25. In particular, I believe that the change "Default to xf86-video-modesetting on GeForce 8 and newer" in xorg-x11-server-Xorg-1.19.3-4 is responsible. Switching /usr/libexec/Xorg to the one in xorg-x11-server-Xorg-1.19.3-1.fc25.x86_64 meant the screen was refreshed properly.

Also I found this issue wasn't present when using another Quadro NVS 295 instead of the AMD GPU to drive the third monitor.