I personally am running a slightly older AMD set up and am having no major issuse with my settings set to high. I would rate my performance as fair to good at these settings and really only have an issue when attempting to use HD settings. I have uploaded my DXdaig as a refernce point for some of the other users having issues on newer machines. I might also suggest comparing the processor architecture for these users as I have had many experiences with friends using bulldozer and piledriver cores from late 2011 to early 2013 in FX series experiencing horrible framerate issues.
Alos, just from my cursory review of the other DX texts, most of the other users are listing the FX-8000 series, which if not the new Vishera core for these, supports the core architecture problem I mentioned. AMD was aware of this and thus why they pushed to revise to the Vishera cores.