DSfix is the most critical mod for PTDE. It allows you to bypass the game's internal 720p rendering limit and unlock or stabilize the frame rate.
Open DSfix.ini with Notepad and apply these "potato" settings for maximum performance: dark souls prepare to die edition low graphics mod
The mod is compatible with the Prepare to Die Edition of Dark Souls, which includes all the DLC. However, players should be aware that the mod may not be compatible with other mods or game versions. DSfix is the most critical mod for PTDE