The issue only appears when the game is allowed to exceed 65FPS. With the game capped at 65FPS via options.txt there is no noticable input lag, but at 66 there is. Disabling G-Sync does not affect this
When my laptop is not plugged in and enters optimal battery life mode, the display switches to 45Hz and the input lag disappears - this affects the game immediately without a restart being required. This also happens when G-Sync is disabled, so either G-Sync doesn't actually disable properly based on options.txt, or there is some other restriction placed on the game in this mode that prevents it from exceeding 65FPS in such case even without G-Sync.
In addition, I have seen the input lag disappear at other times without capping the framerate, but have not been able to reproduce it consistently yet. It's possible that this is affected by an external display I sometimes have connected to the GPU which runs at 60Hz, though I always play the game on the 120Hz built-in display.
System: ASUS ROG G531GU (120Hz 1080p Display; nVidia GTX 1660Ti; Core i5-9300H; 16GB RAM); Windows Build: 19041.804 Minecraft Version: 1.16.201
Alexander Daul Hill
I have some more information from my own tests:
The issue only appears when the game is allowed to exceed 65FPS. With the game capped at 65FPS via options.txt there is no noticable input lag, but at 66 there is. Disabling G-Sync does not affect this
When my laptop is not plugged in and enters optimal battery life mode, the display switches to 45Hz and the input lag disappears - this affects the game immediately without a restart being required. This also happens when G-Sync is disabled, so either G-Sync doesn't actually disable properly based on options.txt, or there is some other restriction placed on the game in this mode that prevents it from exceeding 65FPS in such case even without G-Sync.
In addition, I have seen the input lag disappear at other times without capping the framerate, but have not been able to reproduce it consistently yet. It's possible that this is affected by an external display I sometimes have connected to the GPU which runs at 60Hz, though I always play the game on the 120Hz built-in display.
System: ASUS ROG G531GU (120Hz 1080p Display; nVidia GTX 1660Ti; Core i5-9300H; 16GB RAM);
Windows Build: 19041.804
Minecraft Version: 1.16.201