It wasn't installed so I downloaded version 1.1.4
It didn't fix the issue, thank you for the suggestion though.
Hmm, go ahead and uninstall that (Dual Core Optimizer) then. As you said, it's designed for Windows XP.
As for your issue...well, I experienced stutter recently I solved by doing a clean install of my graphics drivers. You're using an AMD video card, so download the 12.1 Preview Driver here: http://news.softpedia.com/news/Catalyst-12-1-Preview-Get-Custom-modding-Now-Supports-More-GPUs-242509.shtml (2nd link, "modified"),
but don't install it just yet!Go ahead and follow this guide: http://benchmark3d.com/how-to-completely-remove-any-driver to remove AMD Catalyst software and Graphics drivers (JUST that software).
Then install the 12.1 Preview modded drivers.