It has been confirmed from the preview codes of Dark Souls: Prepare To Die Edition that the PC version is locked at 30fps. Yes yes, the one thing we claimed back in June. Not only that, but the internal resolution is locked to 1024×720.

What’s funny here, is that the output resolution can go up to 1080p, however the game will be rendered at 1024×720.

http://www.forbes.com/sites/erikkain/2012/08/09/dark-souls-pc-edition-locked-at-30fps-1024-x-720-internal-resolution/

But the extra content is only half the story of this PC release. In recent weeks, celebrations surrounding this version's announcement have fast turned to worried speculation over how the game performs. This has been spurred on by comments from series director Hidetaka Miyazaki suggesting that From Software's inexperience with the PC format might have an impact on how well the game's been optimised overall.

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There is bad news which could hit PC gamers pretty hit hard, though. While the frame-rate's rough edges have been filed down, you're still going to be playing at 30FPS out of the box, as widely rumoured. A graphics menu has been added in, but there are no obvious ways to raise the bar to the preferable 60FPS mark. In fact, options are pretty meagre overall on this front; you have the standard resolution and refresh rate settings (it does nothing to solve this), and also check-boxes to remove anti aliasing or motion blur. Barebones and to the point.

There's also something curious about the resolution too in that there's no change in clarity when attempting to crank up the settings. On close inspection, it appears that Dark Souls PC uses the very same 1024x720 internal framebuffer as the console versions, regardless of which resolution has been set in the menus. The option provided is for output resolution only; a simple courtesy to allow the game to play on most monitors, but the image quality will always remain the same. In short, PC gamers will very much be getting the genuine console experience here, right down to the pixel.

http://www.eurogamer.net/articles/2012-08-09-dark-souls-pc-preview-the-devils-bargain