Question Rainbow Six Siege Choppy

[narccart]

When I play R6 Siege at 144 Hz it feels choppy but at 120hz it feels smooth, the same thing happens on CS:GO, as soon as I switch back from 120 Hz the gameplay starts to look like it's lagging even though I have high FPS. I am aware I can use G-Sync although I preffer not to since it causes me to have input lag, I'm just wondering why 120 Hz gameplay is completely fine.

Monitor: Asus VG278 27"

RAM: 32 GB DDR4
CPU: AMD Ryzen 5 2600X
GPU: Gigabyte Geforce RTX 2080 Gaming OC 8G
Motherboard: Asus Prime B350M-A
OS: Windows 10 Pro

 

[narccart]

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