Yes, I believe something is going on...
I just bought/setup a brand-new rig back in February of 2014 and my FPS was working perfectly normal, even on High/Ultra settings in Multiplayer mode!!
Then all of a sudden, since this last update (which added the new To-199 Neophron and A-164 Wipeout jet fighters), my FPS went to h*ll on ANY server I join in Multiplayer mode. ---- Singleplayer mode and mission editor work PERFECTLY normal...
Not sure what happened, but my cousin and I hosted/setup a brand new private server and I was experiencing the exact same issue. I even had my video settings to the LOWEST quality possible. I will get max 12 FPS regardless of which server I join, and the game play will be EXTREMELY "choppy"...
What happened? It was all working perfectly fine before all these new updates... should I try re-installing Arma 3 through Steam??
Thanks!
-Modeo
My Rig:
Video Card --- GeForce GTX 760 (2GB)
CPU --- Intel Core i7-4770 Haswell Quad-Core 3.4GHz
RAM --- CORSAIR Vengeance Pro Series 16GB (DDR3-2666)
(not the slowest machine... what is going on~!?!)