Is it making the game itself smoother or the mouse input smoother?
Because if it's making your game smoother, that indicates other issues at play, and is not the mouse issue discussed here. Generally if an FPS cap helps make a game run better it's due to your hardware config. Usually this would be big FPS spikes, so what you're seeing is calmer frametimes and it being more consistent.
This again has no effect on the mouse input issue at play here.
My highest fps is in the firing range, and even then it doesn't hit 125fps. It still only hits 110fps or so. This cap doesn't suddenly match the framrate to the mouse polling, and I'm always below the 125fps cap regardless.
Again, setting the game to something like 60fps has the exact same stutter when moving the mouse as it does at any other cap. 60fps has huge power to spare and is not taxing, yet still a stuttery mess.
Im not sure if you gonna see that on video - https://www.youtube.com/watch?v=19YA_6L4HIE
