Open the C:\GOG Games\Jade Empire\
logs\d3d.log in a text editor (notepad will do) and post the content.
If the log contains the following two lines:
RenderSystem.ApplySettings: Display mode from settings not found, using default!
RenderSystem.ApplySettings: ERROR: Device does not support the default display mode, can't run the game!
...Jade Empire does not find the configured and default display mode (resolution
and refresh rate) while enumerating the display modes.
Open the C:\GOG Games\Jade Empire\
JadeEmpire.ini with a text editor and change
ScrW,
ScrH,
RefreshRate, and optionally
Widescreen in the
[Render] section to match your native desktop mode (run
dxdiag and have a look at the display tab to find the current resolution and refresh rate). All the other relevant options (besides the Frame Rate Limit) can be changed with the in-game options.
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I'm running Jade Empire on Wine and had to setup a refresh rate of 50Hz instead of 60Hz (with DynamicTwinView enabled the binary NVIDIA driver uses the refresh rates as display mode indices when queried over the XRandR 1.1 interface):
[Render]
ScrW=1920
ScrH=1080
RefreshRate=50
Widescreen=1