A dualcore seems way outdated for game tests to me. For ex. if you would try X-Plane with a dualcore it would hardly run at all on all os. As X-Plane performs best on Linux, I'm way surprised to see such. The porting was done by a Mac company hence no wonder it needs a multicore.
PS: yes it fully uses all 8 cores hence I'm not surprised about such FPS on a dated dualcore
Even a i3 is mentioned as minium in the specs and this ridi* arstecnica gaming test site uses a dualcore!