Follow these simple steps.

Step 1: Go to your nvidia settings, go to "change resolution" and create a custom resolution.
Step 2: Set the refresh rate here to 60 (1920x1080 and 60hz).
Step 3: Make sure that the "darksouls.ini" file has the refresh rate set to 60.
Step 4: You can access the ini file in.
Step 5: C:\Users\YourUSERNAME\AppData\Local\FromSoftware\NBGI\DarkSouls.