Serious Sam
HD: Gold Edition
There is a HD: Gold Edition available on Steam, which includes HD remakes of both Serious Sam HD First and Second Encounter, plus the original versions.
Add custom resolution:
In this example we will change the resolution to 1680 x 1050:
Locate PersistentSymbols.ini in
C:\Program Files (x86)\Croteam\Serious Sam the First Encounter\Scripts\
Then change these variables:
persistent extern INDEX sam_iScreenSizeI=(INDEX)1680;
persistent extern INDEX sam_iScreenSizeJ=(INDEX)1050;