I'm experiencing mouse input lag with any settings.
So far I've set mouse smoothing to 0 in cfg, disabled Game Bar/Mode/Captures, fullscreen optimization, HPET, Windows Defender, set priority to High on Dayz_64.exe, tried different mouse DPI/sensitivity and different polling rates - 1000Hz, 500Hz, 125Hz, adjusted time resolution to 1/0.5, played locally without internet, plugged PSU and monitor cables into different wall sockets, removed ASUS Armoury Crate, Razer Cortex, Razer Synapse 3, antivirus programs.

MCLK, UCLK, FCLK are all of 1:1:1 ratio.
XMP enabled.

My PC specs are:
Keyboard - HyperX Alloy Origins Core
Mouse - Razer Naga X
Monitor - LG UltraGear 27GP850-b (165Hz)
Motherboard - ROG STRIX B550-F GAMING WIFI II
CPU - Ryzen 5 5600
GPU - RTX 4070
RAM - G.Skill Trident Z 2x16 DDR4 3600Mhz CL18
PSU - Cooler Master V750

I seriously doubt the problem is on my end as I've tried Rust, Mafia 2 DE, CS2 and I don't have any input lag there whereas DayZ feels sluggish even at 160+ FPS.