I've also been having this issue, when I first got the game, (when it first came out), I would get a solid 144 fps at ultra, now, I can get 144 in SP, but in MP, it tends to drop all the way to 3 fps for no reason. Highest I've gotten is around 55 fps. I also reinstalled and updated my drivers and nothing seems to help. I've also tried lowering the setting from ultra to low, and there is still no change.
Edit: I have reinstalled and updated my GPU drivers to the newest version (378.78) and reinstalled BF1, there has been an fps increase, but i think that would be contributed to the newest drivers giving performance boosts with DX12 on. But the increase in frames was only around 20-30, still lacking heavily compared to the previous frames achieved. I have also monitored CPU, GPU and RAM usage; CPU usage never hit 100 to show bottle necking; GPU was of course ok; RAM was fine also. At this point, I have no idea on what to do.
PC Specs:
Windows 10
i7-6700 @3.40ghz
16GB DDR4 RAM
GTX1080 8GB VRAM
