Before - http://www.abload.de/img/data2012-08-2401-28-0xepj9.png
After - http://www.abload.de/img/data2012-08-2401-24-0c4qnh.png

"If you have a 120Hz monitor, you might run into one of two problems:
Framerate locked at 15Hz, or resolution is locked at 720x540.

The fix is to open up the DarkSouls.ini file and manually set your fullscreen resolution and monitor's framerate there.

The .ini file is located here: C:Users[YourUserName]AppDataLocalNBGIDarkSoulsDarkSouls.ini

Some people have reported that using HDMI rather than DisplayPort also resolves the issue."


"As most of you may know, the Dark Souls port for PC has a fixed rendering resolution of 1024x720. I couldn't believe this when it was first rumoured, and when it turned out true I vowed to do my best to fix it.


What is it?
It's an interception d3d9.dll that you place in the same folder as the game executable. It intercepts the game's calls to the DirectX 9 API and changes them as necessary to enable a higher internal rendering resolution.


How do I use it?
Place d3d9.dll and DSfix.ini into the game's binary directory. (The place where DARKSOULS.exe is)
You can open DSfix.ini with a text editor to adjust the desired internal resolution.


Will it work?
So far, this has only been tested on my computer, on the first half hour or so of the game. I can not and will not guarantee that it will work for anyone else, or not have any adverse effect on your game/computer. Use at your own risk! If you encounter any issues that seem like they could be caused by DSfix, let me know.


Why is it still blurry?
I don't know at this point in time. It's already clear that there is a lot more detail and less aliasing using an increased framebuffer resolution -- as you would expect! -- but there is some residual blur. I'm trying to work out if this is due to my method or something inherent in the game. I will certainly continue working on this.


Will it cause performance problems?
That depends on your system configuration. Usually, performance scales rather linearly with framebuffer size, and so far this game does not seem different. My 660 maintained a locked 30 FPS throughout ~ 1/2 hour of testing in the starting area of the game at 2560x1440."

   -- Compliments of Durante @ http://www.neogaf.com/forum/member.php?u=14988