I found a way to change the resolution in this game, editing the registry keys.
The game, by default, only lets you select 3 resolutions: 640x480, 800x600 and 1024x768.
To play at any other resolution you must :
1- Open regedit and navigate to HKEY_CURRENT_USERSoftwareSierra On-LineGabriel Knight 3Engine
2- edit the decimal value of these keys :
(default) = yyyy
Screen Height = yyyy
Screen Widht = xxxx
Where xxxx is desired width & yyyy is desired height.
(default) and "Screen Height" MUST have the same value.
Some pics:
1920x1080:
1024x768:
1920x1080:
1024x768:
1920x1080:
