Intel I5 4670k @ 4.4 ghz.
16 gb DDR3 @2100 mhz (OC)
GTX 980 TI (Evga Classified ~1430 mhz clock)
Settings for testing AA (Maxed) varying AA from None to Medium.
Low AA has only a slight performance hit. Medium AA has a substantial one.
Everything set to Low (how I normally play for max FPS).
Not much of a delta between low and high settings on my 980 TI. On my 290, I had large performance gains from turning settings down.
I'm coming from a GTX 1060 and before that a 290. The 290 was OC'ed to 390x levels but always generally had microstutter in end-game situations. The GTX 1060 is only suppose to be about 10% faster but perfromed much better in general with less stutter. It was still only 20 FPS at 1440p in end-game situations for me. It's weird how upping settings with Nvidia cards doesn't seem to slow it down much.
To be fair, COH2 performance has actually improved over the last 3 years so that may be on relic's side of things.