Baseline (Widescreen) Solution & Issues
The GOG.com version is pre-patched with NewDark for native widescreen and multi-monitor support; for other versions install the latest stable version of TFix to get the NewDark engine upgrade.
With NewDark all widescreen and multi-monitor resolutions are listed in-game. Menus and FMV cutscenes are letterboxed 4:3. Everything has the correct aspect ratio. The HUD's health bar spacing varies but the individual health units retain the correct proportions.
Some special/custom resolutions may be only listed in-game if the resolution is also being used as the desktop resolution (resolutions can also be set in cam.cfg to get around this).
Ultra/Super-Wide (21:9/32:9) Specific Solution & Issues
Eyefinity / Surround Specific Solution & Issues
Same as widescreen.
Mouse movement in menus is much slower horizontally than vertically (gameplay is not affected).
4k UHD Specific Solution & Issues