for me, this bug appeared 1 month ago, but I don't know if it is related to Nvidia driver or DCS open beta update. Now I'm using native 1080p of my monitor with AA, but FPS os worse than DSR 4k ou 2k.
I'm using GTX1070 8gb, 16gb of ram DDR3 1886 CL10,core I7 2700K @5ghz and Raid 0 of 2x SSD 240GB SATA III. Nvidia driver version is the latest 417.35 and windows 10 pro 64 bits.