3 years later machines are even faster.
I can start have in Windows 10 only with SC3U.exe" -w -r:800x600 on Nvidia, when i try to set other resolution ingame im gettin only small picture.. not full screen with black bars in for 4:3 but original resolution, maybe it can be somehow adjusted by Nvidia panel on per game basic.. I dont want to set it for all game, because for other games its working correctly..
I tried of course SC3U.exe" -w -r:1280x1024.
My screen is 16:10 - 1920:1200
If you want to make sure the game and not the video card/drivers is the problem you need to change the options in the NVidia control panel in 'Display' > 'Adjust desktop size and position' > 'Scaling' tab > select the 'Aspect ratio' radial and activate 'Override the scaling mode set by games and programs' check box.
That last check box especially could be your reason to have other full screen programs run correctly while SC3000 does not.
In case those are already the options selected and the game has the issue you say, then it's a problem between the game, your drivers and the OS. In other words, practically anything.