First of all, it depends on your graphics card if it's possible at all and how to activate it. I can only tell how it's done with the DirectX 12 version on a Nvidia GeForce 970 (so with AMD cards the first part will be different). Unfortunately my system is in German, so the actual English phrasing might be a bit different.
- Open the
NVIDIA SYSTEM SETTINGS
(for this the correct NVIDIA driver need to be installed of course)
- Under
3d settings
go to Surround, PhysX configuration
- Tick the check box under
Surround-Configuration
that should state something like Span over multiple displays with Surround
and click on Config
.
- Select both monitors by ticking the check boxes. Check for the correct monitor alignment. Note the resolution (e.g. 3840 x 1080), and modify if needed. Click
Activate Surround function
, and close the config window.
Now your Windows desktop should be spanned over both monitors!
Next we need to config Civilization VI itself.
- Go to
%USERPROFILE%\Documents\My Games\Sid Meier's Civilization VI\
(if using Windows 10)
- Open
AppOptions.txt
- Set
RenderWidth
and RenderHeight
to the configuration noted above (e.g. 3840 and 1080)
- Set
FullScreen
to 2
- Save the file
Now when you start the game it should run spanned over both monitors!