http://www.techspot.com/review/712-arma-3-benchmarks/page5.html
I would imagine that Skylake would perform better, but when you have a Haswell i7 & an FX-8350 almost neck-and-neck at the same core speeds (53 vs. 48 @ 4GHz, 55 vs. 52 @ 4.5 GHz) with a GTX Titan@1920x1200 Ultra (which isn't as powerful as your 980Ti -- http://anandtech.com/bench/product/1496?vs=1446), that tells me 2 things:
1. ARMA 3 is not a CPU-intensive game (especially when an A10 APU can stay within range of a Haswell i3, & even match 80% of an i7's performance), but rather a GPU intensive game.
2. Your 980Ti is at or right below the top of the heap, so it should have no trouble with getting near-60FPS performance, if not more, at Ultra settings...provided you haven't turned up the resolution too much (http://www.techspot.com/review/712-arma-3-benchmarks/page4.html -- the Titan X drops down to your 30-35FPS range if you crank it up to 2560x1600, & they pretty much recommend a CrossFire or SLI solution in order to get consistent 60+ FPS at the higher resolutions). You need to turn down the resolution down to 1920x1200 or 1680x1050, drop the Quality level from Ultra to Very High, or do both in order to get 60FPS or better performance...or spend a ton of cash on a 2nd 980Ti to run in SLI mode.